Air conditioner and shut-off valve fault detection method thereof

Abstract

The present application proposes an air conditioner and a method for detecting a stop valve fault thereof. The air conditioner includes: a controller for determining the operating parameters of N compressors and the indoor coil temperatures of N indoor heat exchangers when the air conditioner is powered on for the first time and the air conditioner is turned on for heating operation; when the operating parameters of the N compressors and the indoor coil temperatures of the N indoor heat exchangers meet the preset conditions, the compressors are controlled to stop; after the first preset time, the operating parameters of the N compressors and the indoor coil temperatures of the N indoor heat exchangers are determined again; and when the operating parameters of the N compressors and the indoor coil temperatures of the N indoor heat exchangers meet the preset conditions for the preset number of times, the compressors are controlled to stop. The present application can improve the accuracy of the stop valve failure not being opened, reduce the air conditioner lock caused by misjudgment, thereby reducing user complaints, and when the compressor operating parameters and the indoor coil temperature meet the preset conditions, the compressor is controlled to stop without waiting for the overcurrent protection to stop, which can make the protection timing earlier.

Description

Technical Field

[0001] The present application relates to the technical field of air conditioning, and in particular to an air conditioner and a stop valve fault detection method thereof. Background Art

[0002] A split-type air conditioner consists of an indoor unit, an outdoor unit and a connecting pipe, which are connected into a whole during installation. In addition, the air conditioner installation and the whole machine commissioning are separated. If the stop valve is not opened after the air conditioner is installed, and the commissioning personnel do not check whether the stop valve is open during the whole machine commissioning, if the air conditioner is operated for heating when the stop valve is not opened, the compressor may be damaged in a short period of time, or even the pipeline may burst, thus endangering personal safety.

[0003] At present, the protection method for the stop valve is usually to detect whether the stop valve meets the preset conditions. For example, in the stop valve protection control method of patent document CN113587359A, it is disclosed that after the air conditioner is turned on and runs for a certain period of time, it is judged whether the first preset condition for judging the stop valve is met. If it is met, the air conditioner is controlled to stop for a certain period of time and then turned on again. After running for a period of time, it is judged whether the second preset condition for determining that the valve is abnormal is met for the stop valve. If it is met again, it is determined that the valve has a stop abnormality and the corresponding stop valve protection is triggered.

[0004] However, when the stop valve is fault-detected in the above manner, even if the stop valve is open, an overcurrent fault may easily occur due to problems such as indoor motor jam, indoor motor shutdown or extremely low user power supply voltage, thereby causing a misjudgment or missed judgment of the compressor fault. After a misjudgment, the air conditioner is actively stopped and locked, causing user complaints. In addition, the compressor may be damaged if the air conditioner is passively shut down after an overcurrent occurs. Summary of the invention

[0005] The present application aims to solve at least one of the technical problems existing in the prior art.

[0006] To this end, one purpose of the present application is to propose an air conditioner that can improve the accuracy of the shut-off valve not opening fault, reduce the air conditioner lock caused by misjudgment, thereby reducing user complaints, and control the compressor to shut down when the compressor operating parameters and indoor coil temperature meet the preset conditions, without waiting for the overcurrent protection shutdown, which can make the protection timing earlier.

[0007] To this end, a second objective of the present application is to provide a method for detecting a stop valve failure of an air conditioner.

[0008] In order to achieve the above-mentioned purpose, an embodiment of the first aspect of the present application proposes an air conditioner, which includes: a refrigerant circulation loop, so that the refrigerant circulates in the circulation loop among a compressor, a condenser, an expansion valve and an evaporator; an outdoor heat exchanger and an indoor heat exchanger, wherein one works for the condenser and the other works for the evaporator; an indoor coil temperature sensor for detecting the indoor coil temperature; an outdoor unit, wherein the outdoor unit includes: an outdoor casing; a compressor, arranged in the outdoor casing, for compressing low-temperature and low-pressure refrigerant gas into high-temperature and high-pressure refrigerant gas and discharging it to the condenser; a stop valve, wherein the stop valve is arranged in the outdoor casing. A controller is provided in the casing for opening or closing the refrigerant circulation loop; the controller is used to determine the operating parameters of N compressors and the indoor coil temperatures of N indoor heat exchangers when the air conditioner is powered on for the first time and the heating operation is started; when the operating parameters of the N compressors and the N indoor coil temperatures meet the preset conditions, the compressors are controlled to stop, and after the first low temperature preset time, the operating parameters of the N compressors and the N indoor coil temperatures are determined again, and when the operating parameters of the N compressors and the N indoor coil temperatures meet the preset conditions for a preset number of times, it is determined that the stop valve is faulty and the compressors are controlled to stop.

[0009] According to the air conditioner of some embodiments of the present application, when the air conditioner is powered on for the first time and the heating operation is started, the operating parameters of N compressors and N indoor coil temperatures are analyzed. When the stop valve fails to open, the operating parameters of the compressor and the indoor coil temperature meet the preset conditions, while in other faults, such as the indoor AC motor is blocked or shut down due to a fault and the AC power supply voltage is extremely low, the operating parameters of the compressor and the indoor coil temperature do not meet the preset conditions. Therefore, by detecting the operating parameters of the compressor and the indoor coil temperature, and when the operating parameters of the compressor and the N indoor coil temperatures meet the preset conditions for a preset number of times, it is determined that the stop valve has a failure to open, thereby avoiding misjudgment of a fault caused by the compressor shutting down due to usage scenarios such as indoor motor blocking or extremely low power supply voltage, thereby improving the accuracy of the stop valve failure to open, reducing the air conditioner locking caused by misjudgment, thereby reducing user complaints, and when the compressor operating parameters and the indoor coil temperature of the indoor heat exchanger meet the preset conditions, the compressor is controlled to shut down without waiting for the overcurrent protection shutdown, which can make the protection timing earlier.

[0010] In order to achieve the above-mentioned purpose, an embodiment of the second aspect of the present application proposes a method for detecting a stop valve fault of an air conditioner, which method includes: when the power is turned on for the first time and the air conditioner starts heating operation, determining the operating parameters of N compressors and the indoor coil temperatures of N indoor heat exchangers; when the operating parameters of the N compressors and the N indoor coil temperatures meet the preset conditions, controlling the compressors to stop, and after the first low temperature preset time, determining the operating parameters of the N compressors and the N indoor coil temperatures again, and when the operating parameters of the N compressors and the N indoor coil temperatures meet the preset conditions for a preset number of times, determining the stop valve fault and controlling the compressors to stop.

[0011] According to the stop valve fault detection method of the air conditioner in some embodiments of the present application, when the air conditioner is powered on for the first time and the heating operation is started, the operating parameters of N compressors and N indoor coil temperatures are analyzed. When the stop valve fails to open, the operating parameters of the compressor and the indoor coil temperature meet the preset conditions, while in other faults, such as the indoor AC motor is blocked or shut down due to a fault and the AC power supply voltage is too low, the operating parameters of the compressor and the indoor coil temperature do not meet the preset conditions. Therefore, by detecting the operating parameters of the compressor and the indoor coil temperature, and when the operating parameters of the compressor and the N indoor coil temperatures meet the preset conditions for a preset number of times, it is determined that the stop valve has a non-opening fault, thereby avoiding misjudgment of the fault caused by the compressor shutdown due to usage scenarios such as indoor motor blocking or power supply voltage being too low, thereby improving the accuracy of the stop valve failure not opening, reducing the air conditioner lock caused by misjudgment, thereby reducing user complaints, and when the compressor operating parameters and the indoor coil temperature of the indoor heat exchanger meet the preset conditions, the compressor is controlled to shut down without waiting for the overcurrent protection shutdown, which can make the protection timing earlier.

[0012] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0014] Figure 1 is a schematic diagram of the structure of an air conditioner in operation according to some embodiments of the present application;

[0015] Figure 2 (a) is a schematic diagram of the change curves of the indoor coil temperature and the outdoor coil temperature when the stop valve is open according to some embodiments of the present application;

[0016] Figure 2(b) is a schematic diagram of curve changes of exhaust pressure and suction pressure when the stop valve is open according to some embodiments of the present application;

[0017] Figure 2 (c) is a schematic diagram of the curve change of the phase current when the stop valve is open according to some embodiments of the present application;

[0018] Figure 3 (a) is a schematic diagram of the change curves of the indoor coil temperature and the outdoor coil temperature when the stop valve is closed according to some embodiments of the present application;

[0019] Figure 3 (b) is a schematic diagram of curve changes of exhaust pressure and suction pressure when the stop valve is closed according to some embodiments of the present application;

[0020] Figure 3 (c) is a schematic diagram of the curve change of the phase current when the stop valve is closed according to some embodiments of the present application;

[0021] Figure 4 (a) is a schematic diagram of the change curves of the indoor coil temperature and the outdoor coil temperature when the indoor motor is stopped or blocked and the stop valve is in an open state according to some embodiments of the present application;

[0022] Figure 4 (b) is a schematic diagram of the curve changes of the suction pressure and the exhaust pressure when the indoor motor is stopped or blocked and the stop valve is in an open state according to some embodiments of the present application;

[0023] Figure 4 (c) is a schematic diagram of the curve change of the compressor phase current when the indoor motor is stopped or blocked and the stop valve is in an open state according to some embodiments of the present application;

[0024] Figure 5 (a) is a schematic diagram of curve changes of indoor coil temperature and outdoor coil temperature when the AC power supply voltage is extremely low and the stop valve is in an open state according to some embodiments of the present application;

[0025] Figure 5 (b) is a schematic diagram of curve changes of exhaust pressure and suction pressure when the AC power supply voltage is ultra-low and the stop valve is in an open state according to some embodiments of the present application;

[0026] Figure 5 (c) is a schematic diagram of the curve change of the compressor phase current when the AC power supply voltage is extremely low and the stop valve is in an open state according to some embodiments of the present application;

[0027] Figure 6 is a block diagram of an air conditioner according to some embodiments of the present application;

[0028] Figure 7 is a flow chart of a method for detecting a stop valve failure of an air conditioner according to some embodiments of the present application;

[0029] Figure 8 (a) is a schematic diagram of indoor coil temperature and outdoor coil temperature curves when the stop valve is closed according to some embodiments of the present application;

[0030] Figure 8 (b) is a schematic diagram of curve changes of exhaust pressure and suction pressure when the stop valve is closed according to some embodiments of the present application;

[0031] Figure 8 (c) is a schematic diagram of the curve change of the phase current when the stop valve is closed according to some embodiments of the present application;

[0032] Fig. 9 is a flow chart of a method for detecting a stop valve failure of an air conditioner according to some embodiments of the present application;

[0033] Fig.10 (a) is a schematic diagram of the change curves of the indoor coil temperature and the outdoor coil temperature when the stop valve is closed according to some embodiments of the present application;

[0034] Fig.10 (b) is a schematic diagram of the curve structure of the exhaust pressure and the suction pressure when the stop valve is closed according to some embodiments of the present application;

[0035] Fig.10 (c) is a schematic diagram of the curve change of the phase current when the stop valve is closed according to some embodiments of the present application;

[0036] Fig.11 is a flow chart of a method for detecting a fault of an air conditioner stop valve according to some embodiments of the present application;

[0037] Fig.12 4 is a flow chart of a method for detecting a fault of an air conditioner stop valve according to some embodiments of the present application. DETAILED DESCRIPTION

[0038] The embodiments of the present application are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. The embodiments of the present application are described in detail below.

[0039] The air conditioner in this application performs a refrigeration cycle of the air conditioner by using a compressor, a condenser, an expansion valve and an evaporator. The refrigeration cycle includes a series of processes involving compression, condensation, expansion and evaporation, and supplies refrigerant to the air that has been conditioned and heat-exchanged.

[0040] The compressor compresses the refrigerant gas in a high temperature and high pressure state and discharges the compressed refrigerant gas. The discharged refrigerant gas flows into the condenser. The condenser condenses the compressed refrigerant into a liquid phase, and the heat is released to the surrounding environment through the condensation process.

[0041] The expansion valve expands the high-temperature and high-pressure liquid refrigerant condensed in the condenser into a low-pressure liquid refrigerant. The evaporator evaporates the refrigerant expanded in the expansion valve and returns the refrigerant gas in a low-temperature and low-pressure state to the compressor. The evaporator can achieve a refrigeration effect by utilizing the latent heat of evaporation of the refrigerant to exchange heat with the material to be cooled. In the entire cycle, the air conditioner can adjust the temperature of the indoor space.

[0042] The outdoor unit of the air conditioner refers to a part of a refrigeration cycle including a compressor and an outdoor heat exchanger, the indoor unit of the air conditioner includes an indoor heat exchanger, and the expansion valve may be provided in the outdoor unit or the indoor unit.

[0043] The indoor heat exchanger and the outdoor heat exchanger function as a condenser or an evaporator. When the indoor heat exchanger functions as a condenser, the air conditioner functions as a heater in a heating mode, and when the indoor heat exchanger functions as an evaporator, the air conditioner functions as a cooler in a cooling mode.

[0044] The stop valve is arranged inside the outdoor unit housing, and the opening or closing state of the refrigerant circulation circuit is controlled by controlling the opening or closing of the stop valve.

[0045] Based on the basic heating or cooling working principle of the air conditioner, the structure of the air conditioner during operation is illustrated below.

[0046] like Figure 1 FIG. 1 is a schematic diagram of the structure of an air conditioner in operation according to an embodiment of the present application. Figure 1 It can be seen that when the stop valve is not opened and the system is running, for example, when the air conditioner is running in heating mode, the compressor starts. After the compressor starts, the refrigerant, i.e., the coolant, will be sucked from the outdoor heat exchanger to the compressor suction port and continuously discharged from the compressor exhaust port, and the stop valve is closed. At this time, the refrigerant is squeezed between the compressor exhaust port and the stop valve. Since the space between the compressor exhaust port and the stop valve is very small, the exhaust pressure will rise rapidly, far exceeding the upper limit requirement of the compressor specification. Specifically, the suction pressure drops sharply to 0 atmospheric pressure. At this time, the compression ratio also far exceeds the requirements of the compressor specification. For example, for an R32 compressor, the maximum allowable exhaust pressure is ≤4.30MPa, the minimum allowable suction pressure is ≥0.23MPa, and the maximum compression ratio is ≤7.5, where compression ratio = exhaust pressure (absolute pressure) / suction pressure (absolute pressure), which will cause compressor damage in a short time.

[0047] Based on this, the following describes the situation of the stop valve under different working conditions.

[0048] The changes in various parameters of the air conditioner when the stop valve is in the open state are taken as an example to illustrate.

[0049] like Figure 2 (a) is a schematic diagram of the curve change of the indoor coil temperature and the outdoor coil temperature when the stop valve is open in some embodiments of the present application. When the air conditioner is in heating operation and the stop valves are all open, the indoor coil temperature, that is, the coil temperature value of the indoor heat exchanger, rises slowly and tends to be stable, and the maximum value will not exceed the maximum condensing temperature Tcmax. The outdoor coil temperature, that is, the coil temperature value of the outdoor heat exchanger temperature, drops rapidly and tends to be stable, and the minimum value will not be lower than the minimum evaporation temperature Temin. The indoor ambient temperature and the outdoor ambient temperature are both laboratory ambient temperatures, which remain unchanged in theory.

[0050] like Figure 2 (b) is a schematic diagram of the curves of the exhaust pressure and the suction pressure when the stop valve is open in some embodiments of the present application. The exhaust pressure rises slowly and tends to be stable, and the maximum value will not exceed the maximum exhaust pressure Pdmax. The suction pressure first drops rapidly and tends to be stable, and the minimum value will not be lower than the minimum suction pressure Psmin. Among them, the indoor coil temperature is measured by the indoor coil temperature sensor, the outdoor coil temperature is measured by the outdoor coil temperature sensor, the indoor ambient temperature is measured by the indoor ambient sensor, the outdoor ambient temperature is measured by the outdoor ambient sensor, and the phase current of the compressor is measured by the compressor phase current detection circuit. Among them, the condensing temperature corresponding to the maximum exhaust pressure Pdmax is the maximum condensing temperature Tcmax. There are multiple detection circuits for the phase current of the compressor. The three-resistance circuit can directly collect the UVW three-phase current, and the single-resistance sampling circuit can collect the total current and then reconstruct the UVW three-phase current through an algorithm.

[0051] like Figure 2 (c) is a schematic diagram of the curve change of phase current when the stop valve is open in some embodiments of the present application. When the air conditioner is in heating operation and the stop valves are all open, the phase current of the compressor rises slowly and tends to be stable, and the maximum value will not be greater than the maximum phase current value Imax of the air conditioner.

[0052] Depend on Figure 2 It can be seen that when the stop valve is opened, the indoor coil temperature and the outdoor coil temperature change according to a certain change rule, the exhaust pressure and the suction pressure also change according to a certain change rule, and the operating parameters of the compressor, such as the phase current of the compressor, also change according to a certain rule. If the above parameters do not change according to the regular rule when the stop valve is opened, the above parameters are analyzed to determine the cause of the fault when the above parameters are abnormal.

[0053] It is understandable that when the indoor coil temperature, outdoor coil temperature, exhaust pressure, suction pressure and compressor operating parameters are abnormal, there are many situations that cause the operating parameters of the above-mentioned air conditioner to be abnormal, for example, the operating parameter abnormality is caused by the stop valve not being opened, the operating parameter abnormality is caused by the stop valve being opened but the indoor AC motor is blocked or the indoor AC motor fails to shut down, the operating parameter abnormality is caused by the stop valve being opened but the user's AC power supply voltage is extremely low, etc., and in the above situations, the operating parameters of the compressor, such as the phase current increase and the compressor overcurrent protection shutdown, etc., will appear. However, in different situations, there are obvious differences in parameters such as the compressor phase current, the indoor coil temperature change value and the compressor overcurrent protection shutdown time. Therefore, by analyzing the parameters such as the change of the indoor coil temperature, the change of the compressor operating parameters and the time when the compressor overcurrent protection shutdown action occurs, the causes of the abnormal operating parameters of the air conditioner in different situations can be distinguished, so as to avoid the indoor AC motor blocking or failure and the AC power supply voltage being extremely low, which makes the air conditioner operating parameters abnormal, and causes misjudgment of the opening and closing state of the stop valve.

[0054] The following are some examples of situations where abnormal air conditioner operating parameters occur.

[0055] In some embodiments, when the stop valve is not opened, the operating parameters of the air conditioner change as follows:

[0056] like Figure 3 (a) is a schematic diagram of the change curve of the indoor coil temperature and the outdoor coil temperature when the stop valve is closed in some embodiments of the present application. Figure 1 and Figure 3 As shown in (a), when all the stop valves are closed, the refrigerant is compressed between the compressor exhaust port and the rough stop valve. At this time, no refrigerant flows through the indoor heat exchanger, and the refrigerant in the outdoor heat exchanger is quickly extracted. The indoor coil temperature, indoor ambient temperature and outdoor ambient temperature are laboratory temperatures, which theoretically remain unchanged. The outdoor coil temperature first drops rapidly and slightly, then rises slowly, and finally the outdoor coil temperature tends to the outdoor ambient temperature and finally becomes the same as the outdoor ambient temperature.

[0057] like Figure 3(b) is a schematic diagram of the curve structure of the exhaust pressure and the suction pressure in the closed state of the stop valve in some embodiments of the present application. When the air conditioner is in heating operation, all the stop valves are closed. Due to the abnormality of the air conditioner, the exhaust pressure of the compressor rises sharply, and the pressure difference between the suction pressure and the exhaust pressure increases sharply. Among them, the exhaust pressure rises sharply, and the maximum value before the protection shutdown far exceeds the maximum exhaust pressure Pdmax. The suction pressure drops sharply until it drops to 0 atmospheric pressure and stabilizes at 0 atmospheric pressure. At this time, it is equivalent to the outdoor heat exchanger side being in a vacuum state. If the fine stop valve is not sealed tightly or leaks slightly, it is easy to draw in air, further increasing the danger. At this time, 0 atmospheric pressure is significantly lower than the minimum suction pressure Psmin.

[0058] like Figure 3 (c) is a schematic diagram of the curve change of phase current when the stop valve is closed in some embodiments of the present application. When the pressure difference between the suction pressure and the exhaust pressure of the compressor increases sharply, the load of the compressor motor increases sharply, causing the compressor phase current to rise sharply, thereby greatly exceeding the maximum phase current value Imax specified by the air conditioner. At the same time, the increased exhaust pressure and pressure difference are very likely to exceed the use requirements of the compressor, or exceed the use requirements of the controller, resulting in a rapid overcurrent protection fault and shutdown.

[0059] Depend on Figure 3 It can be seen that when the stop valve is not opened and the air conditioner is running in heating mode, since the stop valve is closed, no refrigerant flows through the indoor heat exchanger, the indoor coil temperature will not change significantly, and the pressure difference between the exhaust pressure and the suction pressure of the compressor will increase sharply, causing the load of the compressor motor to increase sharply, resulting in a sharp increase in the operating parameters of the compressor, such as the phase current of the compressor. It can be understood that when the stop valve is not opened, the indoor coil temperature, the operating parameters of the compressor and the operating status of the compressor will undergo obvious changes. Therefore, when detecting whether the stop valve has a failure of not being opened, the indoor coil temperature, the operating parameters of the compressor and the operating status of the compressor are detected, and when the above parameter changes meet the parameter change law when the stop valve is not opened, it is determined whether the cause of the parameter abnormality is that the stop valve is not opened.

[0060] In some embodiments, when the stop valve is in an open state but the indoor AC motor is blocked or fails to shut down, examples are given of changes in various parameters of the air conditioner.

[0061] like Figure 4(a) is a schematic diagram of the curve changes of the indoor coil temperature and the outdoor coil temperature when the stop valve is in the open state in some embodiments of the present application. When the indoor heat exchanger cannot force heat exchange, the indoor coil temperature will rise sharply, and the outdoor coil temperature will first drop, then slowly rise, and finally tend to the outdoor ambient temperature and be the same as the outdoor ambient temperature. It can be understood that the value of the compressor before shutdown will be significantly lower than the value when the stop valve is in the fully closed state, and the compressor shutdown time is also longer than the time when the stop valve is in the fully closed state. At this time, the outdoor coil temperature and suction pressure first drop rapidly, and then gradually stabilize, which is not much different from the curve when the stop valve is in the fully open state. Among them, the AC motor is open-loop controlled, and once the fault stops, the air conditioner can still operate normally.

[0062] like Figure 4 (b) is a schematic diagram of the curve changes of the suction pressure and the exhaust pressure when the stop valve is in the open state in some embodiments of the present application. When the air conditioner is in heating operation and the stop valves are all open, if the indoor AC motor is blocked or shuts down due to a fault, the air conditioner is still operating normally. Since the indoor fan stops, the indoor heat exchanger cannot force heat exchange, causing the exhaust pressure and condensing temperature, i.e., the indoor coil temperature, to rise significantly, thus exceeding the maximum limit. At this time, an overcurrent fault or overload fault may be reported and the air conditioner may shut down.

[0063] like Figure 4 (c) is a schematic diagram of the curve change of the compressor phase current when the stop valve is in the open state in some embodiments of the present application. When the indoor AC motor is blocked or shut down due to a fault, the air conditioner operates normally, the indoor fan stops, and the indoor heat exchanger cannot force heat exchange, so the compressor phase current will also increase significantly.

[0064] Depend on Figure 4 It can be seen that when the air conditioner is running in heating mode, the stop valve is open and the indoor AC motor is blocked or shut down due to a fault, although the compressor operating parameters are abnormal and the compressor shuts down due to an overcurrent fault, the operating parameters of the compressor before shutdown, such as the phase current, are obviously lower than the phase current when the compressor shuts down when the stop valve is not opened, and the shutdown time of the compressor is also significantly longer than the running time of the compressor when the stop valve is not opened. Therefore, when the stop valve is open but the indoor AC motor is blocked or shuts down due to a fault, the operating parameters of the air conditioner are significantly different from those when the stop valve is not opened. By detecting the operating parameters of the compressor, the indoor coil temperature and the shutdown action of the compressor, it can be distinguished whether the current fault is caused by the stop valve not being opened or by the indoor AC motor being blocked or shutting down due to a fault.

[0065] In some embodiments, the changes in various parameters of the air conditioner are exemplified when the shut-off valve is in an open state but the AC power voltage is extremely low.

[0066] like Figure 5 (a) is a schematic diagram of the curve changes of the indoor coil temperature and the outdoor coil temperature when the stop valve is in the open state in some embodiments of the present application. When the air conditioner is in heating operation and the stop valve is in the open state, the indoor coil temperature rises first, and its maximum value will not exceed the maximum condensing temperature Tcmax, the outdoor coil temperature drops first and then rises, and the minimum value of the outdoor coil temperature will not be lower than the minimum evaporation temperature Temin.

[0067] like Figure 5 (b) is a schematic diagram of the curve changes of the exhaust pressure and the suction pressure when the stop valve is in the open state in some embodiments of the present application. When the air conditioner is in heating operation and the stop valve is in the open state, if the user's AC power supply voltage is extremely low, for example, lower than 140V, the speed of the indoor fan and the outdoor fan will decrease, and the circulating air volume passing through the indoor heat exchanger and the outdoor heat exchanger will decrease, reducing the heat exchange. At this time, the exhaust pressure and the condensing temperature will rise significantly, and there is a possibility of exceeding the maximum limit.

[0068] like Figure 5 (c) is a schematic diagram of the curve change of the compressor phase current when the stop valve is in the open state in some embodiments of the present application. When the power supply voltage is ultra-low, the peak current on the AC side may be very large. At this time, there is a certain possibility that the current fault will be reported and the machine will shut down, that is, the compressor phase current will rise sharply. In addition, the power supply of the user's home must be ultra-low voltage at the beginning, and there is a possibility that the power supply will drop sharply during the operation of the air conditioner.

[0069] Depend on Figure 5 It can be seen that when the air conditioner is running in heating mode, the stop valve is open and the user's AC power supply voltage is extremely low, the phase current of the compressor will also be large, that is, there is a certain probability of abnormal conditions such as compressor shutdown. However, there are obvious differences between the above parameters when the abnormality occurs and the parameters when the stop valve is not opened. Therefore, by detecting the operating parameters of the compressor, the indoor coil temperature and the overcurrent protection shutdown action of the compressor when the air conditioner is running in heating mode, it can be accurately determined whether the current parameter abnormality is caused by the stop valve not being opened, or the indoor AC motor being stuck or shutting down due to a fault, or the AC power supply voltage being extremely low, thereby avoiding misjudgment of the stop valve not being opened.

[0070] In some embodiments, by obtaining the indoor initial coil temperature at the time of compressor startup, the indoor coil temperature at the instant before the overcurrent protection shutdown, the size of the compressor operating parameters within the first preset time, and the time of the compressor overcurrent protection shutdown, the above-mentioned operating parameters are analyzed to determine whether the stop valve detection condition is met, and the number of times the stop valve detection condition is met is counted until the stop valve fault count is greater than the preset number of times, accurately determining that the stop valve has a non-opening fault, avoiding missed judgments and misjudgments caused by indoor motor jams, indoor motor stops, or overcurrent protection shutdowns caused by ultra-low voltage of the user power supply, thereby improving the accuracy of the judgment of the stop valve non-opening fault and avoiding misjudgments that lead to user complaints.

[0071] Reference below Figure 6 Describe the air conditioner according to some embodiments of the present application, such as Figure 6 As shown, the air conditioner 1 of some embodiments of the present application includes: a refrigerant circulation loop 11, an outdoor heat exchanger 12, an indoor heat exchanger 13, an indoor coil temperature sensor 14, an outdoor unit 15, an outdoor unit casing 16, a compressor 17, a stop valve 18 and a controller 19, wherein:

[0072] The refrigerant circulation loop 11 allows the refrigerant to circulate in the circulation loop through the compressor 17, the condenser, the expansion valve and the evaporator; the outdoor heat exchanger 12 and the indoor heat exchanger 13, wherein one works for the condenser and the other works for the evaporator; the indoor coil temperature sensor 14 is used to detect the indoor coil temperature; the outdoor unit 15 includes: an outdoor housing 16; a compressor 17; the outdoor heat exchanger 12 and a stop valve 18, wherein the compressor 17 is arranged in the outdoor housing 16, and is used to compress the low-temperature and low-pressure refrigerant gas into a high-temperature and high-pressure refrigerant gas and discharge it to the condenser; the stop valve 18 is arranged in the outdoor unit housing 16, and is used to open or close the refrigerant circulation loop 11; the controller 19 is used to obtain the indoor initial coil temperature at the start-up time of the compressor when the outdoor controller of the air conditioner is powered on for the first time and the air conditioner is turned on for heating operation. It can be understood that the failure of the stop valve 18 not being opened is only detected when the air conditioner is installed or the whole machine is debugged and separated. Therefore, when obtaining the indoor initial coil temperature, it is necessary to obtain it when the outdoor controller of the air conditioner is powered on for the first time.

[0073] After obtaining the indoor initial coil temperature at the time of compressor startup, it is determined whether the stop valve detection condition is met. The stop valve detection condition includes detecting the relationship between the operating parameters of the compressor, such as the phase current of the compressor, and the first preset parameter threshold within a first preset time, and detecting whether the overcurrent protection shutdown action of the compressor is triggered within a second preset time and a third preset time, and detecting the indoor coil temperature and the indoor initial coil temperature at the instant before the compressor overcurrent protection shutdown, and starting to count the stop valve faults when the indoor coil temperature and the indoor initial coil temperature meet the preset conditions. Among them, using the detection of the indoor coil temperature and the indoor initial coil temperature as the detection condition of the stop valve fault can effectively avoid the situation where, when detecting whether the stop valve has a non-opening fault based on the outdoor ambient temperature, the detected outdoor ambient temperature may be too high due to solar radiation, resulting in a misjudgment of the stop valve not opening fault.

[0074] In different time periods, when it is detected that the indoor initial coil temperature and the operating parameters of the compressor, i.e., the overcurrent protection shutdown action of the compressor, meet the stop valve detection condition, the stop valve faults are counted, and after the first low temperature preset time, it is judged again whether the stop valve detection condition is met, that is, the indoor initial coil temperature and the operating parameters of the compressor, i.e., the overcurrent protection shutdown action of the compressor, are detected again, and when the stop valve detection condition is met again, the stop valve faults are counted until the stop valve fault count reaches a preset number of times, and the stop valve fault is determined, wherein the third preset time is greater than the second preset time. By counting the stop valve faults, when the stop valve fault count reaches a preset number of times, for example, twice, it is determined that the stop valve has a non-opening fault, which can avoid occasional abnormal operating parameters and misjudgment of the stop valve non-opening fault.

[0075] In some embodiments, when the controller is powered on for the first time and the air conditioner is operating in heating mode, the indoor ambient temperature and the indoor initial coil temperature at the time of compressor startup are detected and stored, and a determination is made as to whether the air conditioner meets the shut-off valve detection conditions, that is, whether the operating parameters of the compressor, the compressor's overcurrent protection shutdown action, the indoor coil temperature before the overcurrent protection shutdown, and the indoor initial coil temperature at the time of compressor startup meet specific conditions.

[0076] For example, the air conditioner meets the stop valve detection condition, that is, within a first preset time, the operating parameter of the compressor exceeds a first preset parameter threshold, such as Figure 3As shown in (a), within the first preset time, for example, 0-t1 minutes, the operating parameter of the compressor is, for example, the phase current of the compressor, and the first preset parameter is, for example, recorded as I1, that is, within 0-t1 minutes, the phase current of the compressor is greater than I1, and the phase current of the compressor continues to increase with time, and the overcurrent protection shutdown of the compressor is detected to be triggered within the second preset time and the third preset time interval, for example, within t1-t2 minutes, the overcurrent protection shutdown action is detected to be triggered; and the indoor coil temperature at the instant before the overcurrent protection shutdown is, for example, recorded as Tc, and the indoor initial coil temperature is, for example, recorded as Tc0, and it is determined whether the indoor coil temperature Tc and the indoor initial coil temperature Tc0 meet the preset conditions. When the indoor coil temperature Tc and the indoor initial coil temperature Tc0 meet the preset conditions, and when all the above conditions are met, the stop valve faults are counted.

[0077] After the first low temperature preset time reaches, for example, 3 minutes, it is determined again whether the stop valve detection condition is met, and the operating parameters of the compressor, the overcurrent protection shutdown action of the compressor, the coil temperature of the indoor heat exchanger before the overcurrent protection shutdown, and the initial coil temperature of the indoor heat exchanger at the time of compressor startup are again detected to see whether they meet specific conditions. When the stop valve detection condition is met again, the stop valve faults are counted until the stop valve fault count reaches a preset number of times, for example, when it is met twice, it is determined that the stop valve is not open. It can be understood that when the air conditioner is turned on for heating operation, the operating parameters of the compressor, the indoor coil temperature, and the indoor initial coil temperature at the time of compressor startup are detected during the operation of the air conditioner to determine whether the stop valve detection condition is met, and when it is determined that the stop valve detection condition is met, the stop valve faults are counted until the fault count reaches a preset number of times, and it is determined that the stop valve has a non-opening fault, so that the stop valve non-opening fault can be quickly and accurately determined.

[0078] According to the air conditioner 1 of some embodiments of the present application, when the air conditioner is powered on for the first time and the heating operation is started, the indoor initial coil temperature at the time of compressor startup is obtained, and the operating parameters of the compressor, the time when the compressor is shut down for overcurrent protection, the coil temperature of the indoor heat exchanger before shutdown, and the initial coil temperature are detected to determine whether the stop valve detection condition is met, and when the stop valve detection condition is met, the stop valve faults are counted until the fault count reaches a preset number of times, and it is determined that the stop valve has a non-opening fault. Since the stop valve has a non-opening fault, the operating parameters of the compressor, the time when the compressor is shut down for overcurrent protection, and the coil temperature of the indoor heat exchanger before shutdown, and the initial coil temperature all meet the stop valve detection condition. When the indoor AC motor is blocked or shuts down due to a fault, although the compressor overcurrent protection shutdown action and the compressor operating parameters are too large will occur, the time when the overcurrent protection shutdown occurs and the operating parameters of the compressor are compared with the stop valve. When the shut-off valve is not opened, there is an obvious difference, that is, the overcurrent protection shutdown time is longer, and the operating parameters of the compressor are smaller. When the AC power supply voltage is ultra-low, there is a small probability that the overcurrent protection shutdown will occur, but the shutdown time is significantly different from when the shut-off valve is not opened, and the operating parameters of the compressor are smaller than when the shut-off valve is not opened, thereby avoiding misjudgment of faults caused by compressor shutdown due to usage scenarios such as indoor motor jam or ultra-low power supply voltage, and using the indoor coil temperature and the indoor initial coil temperature as the detection conditions for the shut-off valve not opening fault, there is no need to detect the shut-off valve not opening fault by detecting the outdoor ambient temperature, which can effectively avoid the shut-off valve not opening fault detection based on the outdoor ambient temperature. Due to the solar radiation, the detected outdoor ambient temperature will be too high, resulting in misjudgment of the shut-off valve not opening fault, thereby improving the accuracy of the shut-off valve not opening fault while reducing user complaints caused by misjudgment.

[0079] In some embodiments, when the indoor coil temperature and the indoor initial coil temperature meet the preset conditions, the difference between the indoor coil temperature and the indoor initial coil temperature is calculated. By calculating the difference between the indoor coil temperature and the indoor initial coil temperature, when the difference does not exceed the second preset parameter threshold, it is determined that the indoor coil temperature and the indoor initial coil temperature meet the preset conditions. Since when the stop valve is not opened, no refrigerant flows through the indoor heat exchanger, the refrigerant in the outdoor heat exchanger is quickly drawn away, and the indoor coil temperature theoretically remains unchanged. By calculating the difference between the indoor coil temperature and the indoor initial coil temperature, when the difference is less than the second preset parameter threshold, it is considered that the indoor coil temperature remains basically unchanged, and this is used as one of the stop valve detection conditions.

[0080] In some embodiments, the indoor coil temperature is recorded as Tc, the indoor initial coil temperature is recorded as Tc0, and the second preset parameter threshold is recorded as △T1. It is judged whether the indoor coil temperature and the indoor initial coil temperature meet the preset condition, that is, the difference between the indoor coil temperature and the indoor initial coil temperature is calculated, and the magnitude relationship between the difference and the second preset parameter threshold △T1 is compared. When the difference does not exceed the second preset parameter threshold, for example, Tc-Tc0≤△T1, it is considered that the indoor coil temperature and the indoor initial coil temperature meet the preset condition. By detecting the indoor coil temperature and the indoor initial coil temperature, the accuracy of the stop valve fault detection is improved.

[0081] In some embodiments, when the overcurrent protection shutdown action of the compressor is not triggered within the second preset time and the third preset time interval, the compressor is controlled to continue running until the continuous running time of the compressor reaches the fourth movement preset time, and it is no longer judged whether the stop valve detection condition is met, wherein the fourth movement preset time is greater than the third preset time. If the compressor overcurrent protection shutdown action is not detected within the specified time, the running time of the compressor is timed. When the running time reaches the fourth movement preset time, it is considered that the stop valve detection condition is not met, and the stop valve does not have a non-opening fault.

[0082] In some embodiments, when the air conditioner is turned on for heating, if the compressor overcurrent protection shutdown action is not detected within the second preset time and the third preset time interval, the compressor is controlled to remain in the on state, and the continuous operation time of the compressor is timed until the continuous operation time of the compressor reaches the fourth movement preset time, for example, 10 minutes, and it is considered that the stop valve has not failed to open. At this time, the operating parameters of the compressor and the indoor coil temperature value are no longer detected to see if they meet the preset conditions, that is, it is no longer determined whether the stop valve has failed to open, and all data related to the determination of the stop valve failure is cleared. By obtaining the continuous operation time of the compressor and no longer determining whether the stop valve detection conditions are met when the continuous operation time of the compressor reaches the fourth movement preset time, it is possible to avoid misjudgment of stop valve failures caused by external unknown environments and unknown electromagnetic interference, thereby improving the reliability of stop valve determination.

[0083] In some embodiments, when the stop valve detection condition is not met and the fault count of the stop valve has not reached a preset number of times, the compressor is controlled to continue running, and the running time of the compressor is counted until the cumulative running time of the compressor reaches a sixth preset time, and it is no longer judged whether the stop valve detection condition is met, wherein the sixth preset time is greater than the fourth preset time, wherein, when the stop valve detection condition is judged, it is necessary to detect the fault count of the stop valve, if the fault count of the stop valve has not reached the preset number of times, for example, when the fault count of the stop valve is 1, it is considered that the compressor has a shutdown action, but when it is judged again whether the stop valve condition is met, the compressor overcurrent protection shutdown action is not triggered, then the running time of the compressor is counted, and when the cumulative running time of the compressor reaches the sixth preset time, it is considered that the stop valve detection condition is not met, and the stop valve does not have a non-opening fault.

[0084] In some embodiments, when the stop valve detection condition is not met and the stop valve fault count has not reached a preset number of times, the compressor is controlled to continue running and the running time of the compressor is counted until the cumulative running time of the compressor reaches a sixth preset time, for example, 30 minutes. The operating parameters of the compressor and the indoor coil temperature value are no longer detected to see whether they meet the preset conditions. By obtaining the cumulative running time of the compressor and when the cumulative running time of the compressor reaches the sixth preset time, it is no longer determined whether the stop valve detection condition is met. This can avoid misjudgment of stop valve failures caused by unknown external environments and unknown electromagnetic interference, thereby improving the reliability of stop valve determination.

[0085] It is understandable that, under normal circumstances, the stop valve failure to open may only occur once. When the air conditioner is not in use, the user will actively cut off the power to the air conditioner, or even if the indoor unit is powered on, when it is not turned on, the indoor controller will automatically cut off the power to the outdoor controller. Once the outdoor controller is powered off, the operating parameters of the compressor, the coil temperature value of the indoor heat exchanger, and the data of the air conditioner's execution of the stop valve protection strategy will all be lost. Therefore, each time the outdoor controller is powered on again, a detection and judgment process of the stop valve failure to open will be performed.

[0086] In some embodiments, when it is determined that the stop valve is faulty, an alarm signal of the stop valve failure is issued, and the compressor is controlled to shut down and no longer automatically start.

[0087] In some embodiments, when the fault count of the stop valve reaches a preset number of times, for example, twice, it is determined that the stop valve is not open, and an alarm message of a stop valve failure is issued, and the compressor is controlled to no longer start automatically, and the stop valve fault judgment is no longer performed, and all data related to the judgment that the stop valve is not open is cleared.

[0088] In some embodiments, the operating parameters of the compressor include: any one of the phase current of the compressor, the input power of the compressor, the whole input power of the air conditioner, and the whole input current of the air conditioner.

[0089] In some embodiments, the operating parameters of the compressor can be any one of the effective value of the compressor, the compressor input power, the whole machine input power of the air conditioner and the whole machine input current of the air conditioner. It can be understood that when the air conditioner is running in heating mode, the stop valve is closed and the refrigerant is compressed in a very small space, causing the exhaust pressure to rise sharply and the suction pressure to drop sharply, so that the suction and exhaust pressure difference increases sharply, and then causes the system load to increase sharply, and act on the compressor drive control. In the drive control of the compressor, the increase in load may cause the compressor input power to increase, the compressor phase current to increase at the same voltage, the whole machine input power to increase, the whole machine input current to increase at the same voltage, etc. Therefore, any one of the above can be selected as the operating parameter of the compressor.

[0090] At present, the compressor uses a permanent magnet synchronous motor. The general FOC (field-oriented control) algorithm needs to transform the current coordinates to convert the compressor phase current in the rotating coordinate system into the D-axis and Q-axis currents in the stationary coordinate system, and control the D-axis and Q-axis currents. When the phase current of the compressor increases, the corresponding D-axis current and Q-axis current also increase accordingly. The essence of the FOC algorithm is to combine the three-way current vectors and then decompose them into two components perpendicular and parallel to the stationary coordinate system. The D-axis current and Q-axis current can be obtained by calculating and transforming the phase current in the rotating coordinate system through a function, that is, the D-axis current and Q-axis current are the currents after the phase current has undergone coordinate transformation. Therefore, the D-axis current, the Q-axis current or a combination of the D-axis and the Q-axis is used to determine the operating parameters of the compressor.

[0091] For example, within the first preset time, such as 40 seconds, it is detected that the phase current of the compressor exceeds the first preset parameter threshold, such as exceeding 12A, then the phase current of the compressor continues to be detected; it is also possible to detect that the input power of the compressor exceeds the first preset parameter threshold, such as exceeding 4.2W, at 40 seconds, then the input power of the compressor continues to be detected; it is also possible to detect that the whole input power of the air conditioner exceeds the first preset parameter threshold, such as exceeding 4.3W, at 40 seconds, then the whole input power of the air conditioner continues to be detected; it is also possible to detect that the whole input current of the air conditioner exceeds the first preset parameter threshold, such as exceeding 18A, at 40 seconds, then the whole input current of the air conditioner continues to be detected; it is also possible to detect that the Q-axis current of the compressor exceeds the second preset parameter threshold, such as exceeding 10A, at 40 seconds, then the Q-axis current of the compressor continues to be detected.

[0092] For example, within the first preset time, such as 40 seconds, it is detected that the phase current of the compressor exceeds the first preset parameter threshold, such as exceeding 12A, then the phase current of the compressor continues to be detected; it is also possible to detect that the input power of the compressor exceeds the first preset parameter threshold, such as exceeding 4.2W at 40 seconds, then the input power of the compressor continues to be detected; it is also possible to detect that the whole input power of the air conditioner exceeds the first preset parameter threshold, such as exceeding 4.3W at 40 seconds, then the whole input power of the air conditioner continues to be detected; it is also possible to detect that the whole input current of the air conditioner exceeds the first preset parameter threshold, such as exceeding 18A at 40 seconds, then the whole input current of the air conditioner continues to be detected; it is also possible to detect that the Q-axis current of the compressor exceeds the first preset parameter threshold, such as exceeding 10A at 40 seconds, then the Q-axis current of the compressor continues to be detected.

[0093] The following is an example of the fault detection of the stop valve. The parameters of the air conditioner are set as follows:

[0094] The first preset time t1=1min, the third preset time t2=2min, the fourth preset time t3=10min, the sixth preset time t4=30min, the second preset parameter threshold △T1=3°C, and the first preset parameter threshold I1=12A.

[0095] In some embodiments, when the outdoor unit controller is powered on for the first time and the heating operation mode is turned on, the compressor starts. The controller detects the indoor ambient temperature Tin0=20°C, the coil temperature Tc0=21°C of the indoor heat exchanger, the outdoor ambient temperature Tout0=15°C, the coil temperature Te0=15°C, and the exhaust temperature Td0=15°C at the time of compressor startup. And the compressor phase current is detected in real time. If at 40s, it is less than the first preset time t1=1min, and the phase current is detected to be 12A, and the phase current is equal to the first preset parameter threshold I1=12A, then the phase current continues to be detected. At 65s, the controller is triggered to trigger the overcurrent protection shutdown. The coil temperature Tc=21.5°C is detected at the time of shutdown. At this time, Tc-Tc0=21.5-21=0.5℃<△T1=3℃, counted 1 time.

[0096] Restart the compressor after 3 minutes and continue to detect phase current and other data in real time. If the phase current is detected to be 12.2A at 35 seconds, continue to detect the phase current. At 55 seconds, the controller is triggered to trigger the overcurrent protection shutdown. Tc=21.5℃ at the time of shutdown. At this time, Tc-Tc0=21.5-21=0.5℃<△T1=3℃. Count once, count twice cumulatively, report the stop valve failure, and no longer restart automatically.

[0097] In some embodiments, the outdoor unit controller is powered on for the first time, the heating operation mode is turned on, and the compressor is started. The controller detects the indoor ambient temperature Tin0 = 20°C, the temperature of the indoor heat exchanger Tc0 = 21°C, the outdoor ambient temperature Tout0 = 15°C, the coil temperature Te0 = 15°C, and the exhaust temperature Td0 = 15°C at the start time. And the compressor phase current is detected in real time. If the phase current is detected to be 12A at 55s, the phase current is continued to be detected. At 109s, the controller is triggered to trigger the overcurrent protection shutdown. Tc = 53°C at the time of shutdown is detected. At this time, Tc-Tc0 = 53-21 = 32°C>△T1 = 3°C, and the count is 0 times.

[0098] The compressor is restarted after 3 minutes, and the phase current and other data are continuously detected in real time. At 5 minutes, the phase current is detected to be 12.2A. The compressor runs until 10 minutes, and no overcurrent shutdown fault is detected. The stop valve failure is no longer judged in the future.

[0099] According to the air conditioner of some embodiments of the present application, when the air conditioner is powered on for the first time and the heating operation is started, the indoor initial coil temperature at the time of compressor startup is obtained, and the operating parameters of the compressor, the time when the compressor shuts down for overcurrent protection, the coil temperature of the indoor heat exchanger before shutdown, and the initial coil temperature are detected to determine whether the stop valve detection conditions are met, and when the stop valve detection conditions are met, the stop valve faults are counted until the fault count reaches a preset number of times, and it is determined that the stop valve has a non-opening fault. Because when the stop valve is not opened, the operating parameters of the compressor, the time when the compressor shuts down for overcurrent protection, and the coil temperature of the indoor heat exchanger before shutdown, and the initial coil temperature all meet the stop valve detection conditions. When the indoor AC motor is blocked or shuts down due to a fault, although the compressor overcurrent protection shutdown action and the compressor operating parameters being too large may occur, the time when the overcurrent protection shutdown occurs and the compressor operating parameters are compared to when the stop valve is not opened. There is an obvious difference, that is, the overcurrent protection shutdown time is longer, and the operating parameters of the compressor are smaller, and, when the AC power supply voltage is ultra-low, there is a small probability that the overcurrent protection shutdown will occur, but the shutdown time is significantly different from when the stop valve is not opened, and the operating parameters of the compressor are smaller than when the stop valve is not opened, thereby avoiding misjudgment of faults caused by compressor shutdown due to usage scenarios such as indoor motor jam or ultra-low power supply voltage, and using the indoor coil temperature and the indoor initial coil temperature as the detection conditions for the stop valve not opening fault, there is no need to detect the stop valve not opening fault by detecting the outdoor ambient temperature, which can effectively avoid the situation where the stop valve not opening fault is misjudged when detecting whether there is a stop valve not opening fault based on the outdoor ambient temperature due to the detected outdoor ambient temperature being too high due to solar radiation, thereby improving the accuracy of the stop valve not opening fault while reducing user complaints caused by misjudgment.

[0100] The following describes a method for detecting a stop valve failure of an air conditioner according to some embodiments of the present application.

[0101] like Figure 7 As shown, the stop valve fault detection method for an air conditioner in some embodiments of the present application at least includes: step S11 to step S16.

[0102] Step S11, when the air conditioner is powered on for the first time and starts heating operation, the indoor initial coil temperature at the time of compressor startup is obtained.

[0103] Step S12, judging whether the stop valve detection condition is met, wherein the stop valve detection condition includes: detecting that the operating parameter of the compressor is greater than the first preset parameter threshold within the first preset time, and detecting that the overcurrent protection shutdown action of the compressor is triggered within the second preset time and the third preset time interval, and determining the indoor coil temperature and the indoor initial coil temperature at the instant before the overcurrent protection shutdown.

[0104] Step S13: When the stop valve detection condition is met, the stop valve failures are counted.

[0105] Step S14, after the first low temperature preset time, it is determined again whether the stop valve detection condition is met.

[0106] Step S15, when the stop valve detection condition is met, the stop valve failure is counted until the stop valve failure count reaches a preset number of times, and the stop valve failure is determined, wherein the third preset time is greater than the second preset time.

[0107] Step S16, when it is determined again that the stop valve detection condition is not met, it is determined that the stop valve does not have a closed fault.

[0108] According to the stop valve fault detection method for air conditioners in some embodiments of the present application, when the air conditioner is powered on for the first time and the heating operation is started, the indoor initial coil temperature at the time of compressor startup is obtained, and the operating parameters of the compressor, the time when the compressor is shut down for overcurrent protection, the coil temperature of the indoor heat exchanger before shutdown, and the initial coil temperature are detected to determine whether the stop valve detection conditions are met, and when the stop valve detection conditions are met, the stop valve faults are counted until the fault count reaches a preset number of times, and it is determined that the stop valve has a non-opening fault. Since the stop valve has a non-opening fault, the operating parameters of the compressor, the time when the compressor is shut down for overcurrent protection, and the coil temperature of the indoor heat exchanger before shutdown, and the initial coil temperature all meet the stop valve detection conditions. When the indoor AC motor is blocked or shut down due to a fault, although the compressor overcurrent protection shutdown action and the compressor operating parameters being too large will occur, the time when the overcurrent protection shutdown occurs and the compressor operating parameters are relatively There is a significant difference compared to when the stop valve is not opened, that is, the overcurrent protection shutdown time is longer and the operating parameters of the compressor are smaller, and, when the AC power supply voltage is ultra-low, there is a small probability that an overcurrent protection shutdown will occur, but the shutdown time is significantly different from when the stop valve is not opened, and the operating parameters of the compressor are smaller than when the stop valve is not opened, thereby avoiding misjudgment of faults caused by compressor shutdown due to usage scenarios such as indoor motor jam or ultra-low power supply voltage, and using the indoor coil temperature and the indoor initial coil temperature as detection conditions for the stop valve failure to open fault, without detecting the outdoor ambient temperature to detect the stop valve failure to open fault, which can effectively avoid the situation where the stop valve is not opened fault detected based on the outdoor ambient temperature, and the outdoor ambient temperature is detected to be too high due to solar radiation, resulting in misjudgment of the stop valve failure to open fault, thereby improving the accuracy of the stop valve failure to open fault while reducing user complaints caused by misjudgment.

[0109] In some embodiments, determining whether the indoor coil temperature and the indoor initial coil temperature meet preset conditions includes: calculating the difference between the indoor coil temperature and the indoor initial coil temperature; and when the difference does not exceed a preset parameter threshold, determining that the indoor coil temperature and the indoor initial coil temperature meet the preset conditions.

[0110] In some embodiments, after the overcurrent protection shutdown of the compressor is not triggered within the second preset time and the third preset time interval, it also includes: controlling the compressor to continue running until the continuous running time of the compressor reaches a fourth movement preset time, and no longer judging whether the stop valve detection condition is met, wherein the fourth movement preset time is greater than the third preset time.

[0111] In some embodiments, after the stop valve detection condition is not met and the fault count of the stop valve has not reached a preset number of times, it also includes: controlling the compressor to continue running, and timing the running time of the compressor until the cumulative running time of the compressor reaches a sixth preset time, and no longer judging whether the stop valve detection condition is met, wherein the sixth preset time is greater than the fourth preset time.

[0112] In some embodiments, Figure 8 As shown, it is a schematic diagram of curve changes when the stop valve fails to open in some embodiments of the present application. Since the present application has a low temperature stop valve detection condition, after the compressor is restarted, the compressor has been preheated, and the exhaust pressure and the operating parameters of the compressor will rise sharply in a short time.

[0113] In some embodiments of the present application, the outdoor ambient temperature and the indoor initial coil temperature at the time of compressor startup are obtained to determine whether the low-temperature stop valve detection condition is met, and when the low-temperature stop valve detection condition is met, the compressor is controlled to stop, and the stop valve fault is temporarily counted. By adding the low-temperature detection condition of the outdoor ambient temperature, when judging the stop valve failure, the misjudgment of the stop valve caused by the outdoor ambient temperature being too low can be taken into account to reduce missed judgments. It can be understood that when the outdoor ambient temperature is too low, even if the stop valve failure occurs, when the air conditioner is operated for the first time, the operating parameters of the air conditioner, such as the compressor operating parameters and the exhaust pressure, are established slowly, and it is impossible to determine whether the stop valve detection condition is met within the specified time, so that the stop valve failure count is inaccurate and missed judgments occur. Therefore, adding the low-temperature stop valve detection condition and temporarily counting the stop valve failure can avoid missed judgments of stop valve failures caused by low outdoor temperatures, and determine whether the stop valve detection condition is met to eliminate the misjudgment of the stop valve failure caused by outdoor motor jam or ultra-low power supply voltage, thereby improving the accuracy of the stop valve failure and reducing user complaints caused by misjudgments.

[0114] Reference below Figure 6 Describe the air conditioner according to some embodiments of the present application, such as Figure 6 As shown, the air conditioner 1 of some embodiments of the present application includes: a refrigerant circulation loop 11, an outdoor heat exchanger 12, an indoor heat exchanger 13, an indoor coil temperature sensor 14, an outdoor unit 15, an outdoor unit casing 16, a compressor 17, a stop valve 18 and a controller 19, wherein:

[0115] The refrigerant circulation loop 11 allows the refrigerant to circulate in the circulation loop through the compressor, condenser, expansion valve and evaporator; an outdoor heat exchanger and an indoor heat exchanger, wherein one works for the condenser and the other works for the evaporator; an indoor coil temperature sensor for detecting the indoor coil temperature; an outdoor unit, the outdoor unit comprising: an outdoor unit casing; a compressor, arranged in the outdoor unit casing, for compressing low-temperature and low-pressure refrigerant gas into high-temperature and high-pressure refrigerant gas and discharging it to the condenser; a stop valve, the stop valve being arranged in the outdoor unit casing, for opening or closing The refrigerant circulation loop; the controller 19 is used to obtain the outdoor ambient temperature and the indoor initial coil temperature at the start-up time of the compressor when the power is turned on for the first time and the air conditioner is turned on for heating. After obtaining the outdoor ambient temperature, if the outdoor ambient temperature does not exceed the preset temperature threshold, it is considered that the current state is in a low temperature condition, and it is determined whether the low temperature stop valve detection condition is met. When the low temperature stop valve detection condition is met, the compressor is controlled to stop, and the stop valve faults are temporarily counted. In the low temperature condition and when the low temperature stop valve detection condition is met, the stop valve faults are temporarily counted to avoid missed judgments caused by low temperature.

[0116] The stop valve is shut down, and after a first low-temperature preset time, the compressor is restarted to determine whether the stop valve detection condition is met, and when the stop valve detection condition is met, the stop valve fault count is counted. After restarting the compressor, if the stop valve detection condition is met, the stop valve temporary count is considered valid; after restarting the compressor, if the stop valve detection condition is not met, the stop valve temporary count is considered invalid, and when the stop valve fault temporary count and the stop valve fault count meet the preset times, the stop valve fault is determined. Taking into account the low-temperature working condition, the stop valve temporary count is increased to improve the accuracy of the stop valve failure that is not opened.

[0117] In some embodiments, the indoor ambient temperature at the time of compressor startup is recorded as Tin0, the initial indoor coil temperature is recorded as Tc0, the outdoor ambient temperature is recorded as Tout0, and the outdoor coil temperature is recorded as Te0. When the outdoor controller of the air conditioner is powered on for the first time and the air conditioner is in heating operation, the outdoor ambient temperature Tout0 and the indoor initial coil temperature Tc0 at the time of compressor startup are obtained. If the outdoor ambient temperature does not exceed the preset temperature threshold, for example, when Tout0 < T1, it is considered that the outdoor ambient temperature is low. At this time, it is determined whether the low-temperature stop valve detection condition is met, that is, it is determined that within the second preset time and the third preset time interval, the operating parameters of the compressor exceed the first preset parameter threshold, and the indoor coil temperature and the indoor initial coil temperature are greater than or equal to the indoor initial coil temperature. When the temperature meets the preset conditions and the operating frequency of the compressor exceeds the second preset parameter threshold, and when the outdoor environment does not exceed the preset temperature threshold, the operating parameters of the compressor exceed the first preset parameter threshold, the indoor coil is stable and the indoor initial coil temperature meets the preset conditions and the operating frequency of the compressor exceeds the second preset parameter threshold, it is considered that the low-temperature stop valve detection conditions are met. It can be understood that when the low-temperature stop valve detection conditions are met, temporary counting of stop valve faults can solve the problem of misjudgment of the stop valve not opening fault due to the low outdoor temperature, the slow exhaust pressure buildup and the slow change of the compressor operating parameters when the compressor is cold started for the first time, thereby reducing missed judgments. Therefore, when making a stop valve fault judgment, low-temperature detection is performed first to reduce the probability of missed judgments.

[0118] After determining that the low-temperature stop valve detection conditions are met, the compressor is controlled to shut down actively to avoid failure to trigger the compressor overcurrent protection shutdown action within the specified time, causing damage to the compressor, and restart the compressor after the first low-temperature preset time, for example, 3 minutes, and judge whether the stop valve detection conditions are met, and judge again whether the stop valve detection conditions are met. When it is determined that the stop valve detection conditions are met again, the stop valve fault temporary count is considered valid, otherwise, the stop valve fault temporary count is considered invalid.

[0119] Determine whether the stop valve detection condition is met, that is, determine whether the operating parameter of the compressor is detected to exceed the first preset parameter threshold within the fourth movement preset time; trigger the overcurrent protection shutdown within the fourth movement preset time and the sixth preset time interval; determine the indoor coil temperature and the indoor initial coil temperature at the instant before the overcurrent protection shutdown, and when the indoor coil temperature and the indoor initial coil temperature meet the preset conditions and the sixth preset time does not exceed the second preset time, determine that the stop valve condition is met, at this time, determine that the stop valve fault temporary count is valid, and count the stop valve times, and when the stop valve temporary count and the stop valve fault count meet the preset times, for example, twice, determine that the stop valve fault is.

[0120] For example, taking the compressor operating parameter as the compressor phase current, the second preset time is recorded as t1, the third preset time is recorded as t2, the first preset parameter threshold is recorded as I1, the indoor coil temperature is recorded as Tc, the indoor initial coil temperature is recorded as Tc0, the compressor operating frequency is recorded as F, the second preset frequency parameter threshold is recorded as F1, the fourth movement preset time is, for example, 0-t3 minutes, and the sixth preset time is t4.

[0121] When the air conditioner outdoor controller is powered on for the first time and the air conditioner is turned on for heating, if the outdoor ambient temperature Tout0 is less than T1, the running time of the compressor is in the range of t1 to t2, the phase current of the compressor is greater than or equal to I1, the indoor coil temperature and the indoor initial coil temperature meet the preset conditions, and the operating frequency F of the compressor is greater than or equal to F1, it is determined that the low-temperature stop valve detection conditions are met, and it is judged that the stop valve may have a failure of not opening, and the compressor is controlled to shut down actively.

[0122] After the first low-temperature preset time, the compressor is restarted. When the start-up time of the compressor is in the interval of 0-t3 minutes, the phase current of the compressor is greater than or equal to the first preset parameter I1. After that, the current continues to increase with time. In the interval from t3 to t4, it is detected that the overcurrent protection shutdown is triggered, and the indoor coil temperature and the indoor initial coil temperature before the overcurrent protection shutdown are obtained. When the indoor coil temperature and the indoor initial coil temperature meet the preset conditions, and the sixth preset time t4 is less than or equal to the second preset time t1, it is considered that the stop valve temporary count is valid, and the number of stop valve failures is accumulated. At this time, it is considered that the stop valve failure count and the stop valve failure temporary count meet the preset times, for example, twice, and the stop valve failure is determined.

[0123] According to the air conditioner of some embodiments of the present application, when the air conditioner is powered on for the first time and the heating operation is started, the outdoor ambient temperature is detected to determine whether the low-temperature stop valve detection condition is met. By determining whether the low-temperature stop valve detection condition is met and temporarily counting the stop valve faults, the problem of misjudgment of the stop valve not opening fault caused by the slow exhaust pressure establishment and slow change of the compressor operating parameters when the compressor is cold started for the first time due to the outdoor temperature being too low can be solved, thereby reducing missed judgments, and after the low-temperature stop valve detection condition is met, it is determined whether the stop valve detection condition is met, and when the above detection conditions are all met, the stop valve faults are counted until the stop valve fault count and the stop valve fault temporary count reach a preset number of times, and it is determined that the stop valve has a non-opening fault. When determining whether the stop valve detection condition is met, since when the stop valve has a non-opening fault, there is a difference between the operating parameters of the air conditioner and the operating parameters when the indoor motor is blocked or the power supply voltage is extremely low, by detecting whether the stop valve detection condition is met, it is possible to avoid misjudgment of the fault caused by the compressor shutdown due to usage scenarios such as indoor motor blocking or extremely low power supply voltage, thereby improving the accuracy of the stop valve not opening fault and reducing user complaints caused by misjudgment.

[0124] In some embodiments, determining whether the low-temperature stop valve detection conditions are met includes, within the second preset time and the third preset time interval, the operating parameters of the compressor exceed the first preset parameter threshold, and the indoor coil temperature and the indoor initial coil temperature meet the preset conditions, and the operating frequency of the compressor exceeds the second preset frequency parameter threshold. By detecting the operating parameters of the compressor, the indoor coil temperature and the indoor initial coil temperature and the operating frequency of the compressor, it can be determined whether the low-temperature stop valve detection conditions are met based on the above parameters.

[0125] In some embodiments, under low temperature conditions in winter, if the stop valve is not opened, when the outdoor unit controller is powered on for the first time and the air conditioner starts the heating mode, the increase rate of the compressor's operating parameters is significantly lower than the increase rate of the compressor's operating parameters when it is started again or multiple times.

[0126] Under low-temperature external conditions, if the compressor is started in a cold state for the first time, the exhaust pressure is relatively slow to build up, and the corresponding compressor phase current rise also changes. At this time, the overcurrent protection shutdown will not be triggered within the specified time, for example, within the sixth preset time and the seventh preset time interval. At this time, if it is not determined whether the low-temperature stop valve detection conditions are met, it is easy to determine that the stop valve has not failed to open when the air conditioner is running at low temperature for the first time, thereby causing the failure of the stop valve to be missed. It is understandable that for low-temperature or ultra-low-temperature conditions, if the overcurrent protection shutdown is detected within the specified time period, a missed judgment will occur, resulting in a late judgment time. Since the failure of the stop valve to open is very dangerous, it is necessary to determine whether the compressor has a failure to open in the shortest possible time.

[0127] After the compressor is started once, it has been preheated, and the exhaust pressure and the phase current of the compressor will rise sharply in a short time. In order to avoid misjudgment of the stop valve not opening fault, it is necessary to make relevant judgments based on the curve of the stop valve not opening fault under normal temperature conditions.

[0128] In some embodiments, when judging whether the stop valve detection condition is met, the length of the sixth preset time and the second preset time must be detected. If the sixth preset time exceeds the second preset time, it is determined that the temporary count of the stop valve failure is invalid, and it is judged again whether the stop valve detection condition is met. When the number of stop valve failures meets the preset number, it is determined that the stop valve is faulty.

[0129] In some embodiments, when determining whether the stop valve detection condition is met, if the sixth preset time exceeds the second preset time, it is considered that no overcurrent protection shutdown is detected within the preset time period, or the duration of the overcurrent protection shutdown being detected is too long. At this time, it is determined that the stop valve fault temporary count is invalid, and then it is determined again whether the stop valve detection condition is met, and when the stop valve fault count reaches a preset number of times, for example, twice, the stop valve fault is determined.

[0130] In some embodiments, when the indoor coil temperature and the indoor initial coil temperature meet the preset conditions, the difference between the indoor coil temperature and the indoor initial coil temperature is calculated. By calculating the difference between the indoor coil temperature and the indoor initial coil temperature, when the difference is less than the second preset parameter threshold, it is determined that the indoor coil temperature and the indoor initial coil temperature meet the preset conditions. Since no refrigerant flows through the indoor heat exchanger when the stop valve is not opened, the refrigerant in the outdoor heat exchanger is quickly drawn away, and the indoor coil temperature theoretically remains unchanged. By calculating the difference between the indoor coil temperature and the indoor initial coil temperature, when the difference is less than the second preset parameter threshold, it is considered that the indoor coil temperature remains basically unchanged, and this is used as one of the stop valve detection conditions.

[0131] In some embodiments, it is determined whether the indoor coil temperature and the indoor initial coil temperature meet the preset condition, that is, the difference between the indoor coil temperature and the indoor initial coil temperature, such as Tc-Tc0, is calculated, and the difference between the two is compared with a second preset parameter threshold, such as the relationship between the difference and △T1. When Tc-Tc0≤△T1, it is considered that the indoor coil temperature and the indoor initial coil temperature meet the preset condition. By comparing the relationship between the difference between the indoor coil temperature and the indoor initial coil temperature and △T1, the accuracy of determining the stop valve failure is improved.

[0132] In some embodiments, when the low-temperature stop valve detection condition is not met, the compressor is controlled to continue running until the continuous running time of the compressor reaches the seventh preset time, and the stop valve failure to open fault is no longer judged, wherein the seventh preset time is greater than the third preset time. If the compressor overcurrent protection shutdown action is not detected within the specified time, the running time of the compressor is timed. When the running time reaches the seventh preset time, it is considered that the stop valve detection condition is not met and the stop valve does not have a failure to open.

[0133] In some embodiments, when the air conditioner is turned on for heating operation, if the low-temperature stop valve detection condition is not met, at this time, the compressor is controlled to remain in the on state, and the continuous operation time of the compressor is timed until the continuous operation time of the compressor reaches the seventh preset time, for example, 10 minutes, it is considered that the stop valve has not failed to open. At this time, the operating parameters of the compressor and the indoor coil temperature value are no longer detected to see if they meet the preset conditions, that is, it is no longer determined whether the stop valve has failed to open, and all data related to the determination of the stop valve failure is cleared. By obtaining the continuous operation time of the compressor, and when the continuous operation time of the compressor reaches the seventh preset time, it is no longer determined whether the stop valve detection condition is met, it is possible to avoid misjudgment of stop valve failure caused by external unknown environment and unknown electromagnetic interference, thereby improving the reliability of stop valve determination.

[0134] In some embodiments, when it is determined that the stop valve detection condition is not met, the compressor is controlled to continue running, and the running time of the compressor is counted until the cumulative running time of the compressor reaches an eighth preset time, and the stop valve failure to open fault is no longer judged, wherein the eighth preset time is greater than the seventh preset time, wherein, when the stop valve detection condition is judged, it is necessary to detect the fault count of the stop valve, if the fault count of the stop valve does not reach the preset number of times, for example, when the fault count of the stop valve is 1, it is considered that the compressor has a shutdown action, but when it is judged again whether the stop valve condition is met, the compressor overcurrent protection shutdown action is not triggered, then the running time of the compressor is counted, and when the cumulative running time of the compressor reaches the eighth preset time, it is considered that the stop valve detection condition is not met, and the stop valve does not have a failure to open.

[0135] In some embodiments, when the stop valve detection condition is not met and the stop valve fault count has not reached a preset number of times, the compressor is controlled to continue running and the running time of the compressor is counted until the cumulative running time of the compressor reaches a ninth preset time, for example, 30 minutes. The operating parameters of the compressor and the indoor coil temperature value are no longer detected to see whether they meet the preset conditions. By obtaining the cumulative running time of the compressor and when the cumulative running time of the compressor reaches the eighth preset time, it is no longer determined whether the stop valve detection condition is met. This can avoid misjudgment of stop valve failures caused by unknown external environments and unknown electromagnetic interference, thereby improving the reliability of stop valve determination.

[0136] It is understandable that, under normal circumstances, the stop valve failure to open may only occur once. When the air conditioner is not in use, the user will actively cut off the power to the air conditioner, or even if the indoor unit is powered on, when it is not turned on, the indoor controller will automatically cut off the power to the outdoor controller. Once the outdoor controller is powered off, the operating parameters of the compressor, the coil temperature value of the indoor heat exchanger, and the data of the air conditioner's execution of the stop valve protection strategy will all be lost. Therefore, each time the outdoor controller is powered on again, a detection and judgment process of the stop valve failure to open will be performed.

[0137] In some embodiments, when it is determined that the stop valve is faulty, an alarm signal of the stop valve failure is issued, and the compressor is controlled to shut down and no longer automatically start.

[0138] In some embodiments, when the fault count of the stop valve reaches a preset number of times, for example, twice, it is determined that the stop valve is not open, and an alarm message of a stop valve failure is issued, and the compressor is controlled to no longer start automatically, and the stop valve fault judgment is no longer performed, and all data related to the judgment that the stop valve is not open is cleared.

[0139] In some embodiments, the compressor operating parameter includes: any one of the phase current of the compressor, the input power of the compressor, the whole input power of the air conditioner, and the whole input current of the air conditioner.

[0140] In some embodiments, the operating parameters of the compressor can be any one of the effective value of the compressor, the compressor input power, the whole machine input power of the air conditioner and the whole machine input current of the air conditioner. It can be understood that when the air conditioner is running in heating mode, the stop valve is closed and the refrigerant is compressed in a very small space, causing the exhaust pressure to rise sharply and the suction pressure to drop sharply, so that the suction and exhaust pressure difference increases sharply, and then causes the system load to increase sharply, and act on the compressor drive control. In the drive control of the compressor, the increase in load may cause the compressor input power to increase, the compressor phase current to increase at the same voltage, the whole machine input power to increase, the whole machine input current to increase at the same voltage, etc. Therefore, any one of the above can be selected as the operating parameter of the compressor.

[0141] At present, the compressor uses a permanent magnet synchronous motor. The general FOC algorithm needs to transform the coordinate of the current to convert the compressor phase current in the rotating coordinate system into the D-axis and Q-axis currents in the stationary coordinate system, and control the D-axis and Q-axis currents. When the phase current of the compressor increases, the corresponding D-axis current and Q-axis current also increase accordingly. The essence of the FOC algorithm is to combine the three-way current vectors and then decompose them into two components that are perpendicular and parallel to the stationary coordinate system. The D-axis current and Q-axis current can be obtained by calculating and transforming the phase current in the rotating coordinate system through a function, that is, the D-axis current and Q-axis current are the currents after the phase current has undergone coordinate transformation. Therefore, the D-axis current, the Q-axis current or a combination of the D-axis and the Q-axis is used to determine the operating parameters of the compressor.

[0142] The phase current of the compressor is usually a sine wave. There are two descriptions of the magnitude of the sine wave current value: one is the effective value of the current and the other is the peak value of the current. The effective value of the phase current is the root mean square value of the current, and the peak value of the phase current is the instantaneous maximum value of the current within a certain period of time. When the controller controls according to the detected current value, it will always detect the instantaneous value of the phase current and compare it to obtain the instantaneous maximum value of the current within a certain time period, that is, the phase current peak value; it will also perform root mean square calculation based on the peak value to obtain the operating parameter value of the compressor.

[0143] For example, within the first preset time, such as 40 seconds, it is detected that the phase current of the compressor exceeds the first preset parameter threshold, such as exceeding 12A, then the phase current of the compressor continues to be detected; it is also possible to detect that the input power of the compressor exceeds the first preset parameter threshold, such as exceeding 4.2W, at 40 seconds, then the input power of the compressor continues to be detected; it is also possible to detect that the whole input power of the air conditioner exceeds the first preset parameter threshold, such as exceeding 4.3W, at 40 seconds, then the whole input power of the air conditioner continues to be detected; it is also possible to detect that the whole input current of the air conditioner exceeds the first preset parameter threshold, such as exceeding 18A, at 40 seconds, then the whole input current of the air conditioner continues to be detected; it is also possible to detect that the Q-axis current of the compressor exceeds the second preset parameter threshold, such as exceeding 10A, at 40 seconds, then the Q-axis current of the compressor continues to be detected.

[0144] For example, within the first preset time, such as 40 seconds, it is detected that the phase current of the compressor exceeds the first preset parameter threshold, such as exceeding 12A, then the phase current of the compressor continues to be detected; it is also possible to detect that the input power of the compressor exceeds the first preset parameter threshold, such as exceeding 4.2W at 40 seconds, then the input power of the compressor continues to be detected; it is also possible to detect that the whole input power of the air conditioner exceeds the first preset parameter threshold, such as exceeding 4.3W at 40 seconds, then the whole input power of the air conditioner continues to be detected; it is also possible to detect that the whole input current of the air conditioner exceeds the first preset parameter threshold, such as exceeding 18A at 40 seconds, then the whole input current of the air conditioner continues to be detected; it is also possible to detect that the Q-axis current of the compressor exceeds the first preset parameter threshold, such as exceeding 10A at 40 seconds, then the Q-axis current of the compressor continues to be detected.

[0145] The following is an example of the fault detection of the stop valve. The parameters of the air conditioner are set as follows:

[0146] The second preset time t1=3min, the third preset time t2=6min, the fourth movement preset time t3=1min, the sixth preset time t4=3min, the seventh preset time t5=10min, the eighth preset time t6=30min, the second preset parameter threshold △T1=3℃, the preset temperature threshold T1=0℃, the first preset parameter threshold I1=12A, the second preset frequency parameter threshold F1=50Hz.

[0147] In some embodiments, when the outdoor unit controller is powered on for the first time, the air conditioner starts heating operation, and the compressor starts, the controller detects the compressor start-up time, indoor ambient temperature Tin0=10°C, indoor initial coil temperature Tc0=11°C, outdoor ambient temperature Tout0=-7°C, outdoor coil temperature Te0=-7°C, and exhaust temperature Td0=-7°C. And the phase current of the compressor is detected in real time. If the compressor phase current I=12.2A is detected at the 5th minute 25s after 3 minutes, the operating frequency of the compressor F=90Hz, and the indoor coil temperature Tc=10°C, that is, Tc-Tc0=10-11=-1°C. Since 5min25s is less than 6min, and at this time I>12A, F>50Hz, (Tc-Tc0)<3°C, the compressor is actively stopped and temporarily counted once.

[0148] 3min restart the compressor, continue to detect phase current and other data in real time, if at 35s, it is less than the fourth movement preset time t3=1min, and the phase current is detected to be 12.2A, then continue to detect the phase current, if at 55s, it is less than the seventh preset time t4=3min, trigger the controller to trigger the overcurrent protection shutdown, and detect the shutdown time Tc=21.5℃. At this time, Tc-Tc0=21.5-21=0.5℃<△T1=3℃, count 1 time. Since the time of the fault shutdown is 55s<the time of the first power-on active shutdown time 5min25s, the first count is valid. At this time, the cumulative count is 2 times, reporting the stop valve failure, and it will not restart automatically.

[0149] In some embodiments, the outdoor unit controller is powered on for the first time, the air conditioner starts heating operation, and the compressor starts. The controller detects the indoor ambient temperature Tin0=10°C, the indoor initial coil temperature Tc0=11°C, the outdoor ambient temperature Tout0=-7°C, the outdoor coil temperature Te0=-7°C, and the exhaust temperature Td0=-7°C at the start time. And the compressor phase current is detected in real time. If the compressor phase current I=12.2A is detected at the 5th minute 25s after 3 minutes, the compressor operating frequency F=90Hz, and the indoor coil temperature Tc=10°C, that is, Tc-Tc0=10-11=-1°C, since 5min25s is less than 6min, and at this time I>12A, F>50Hz, (Tc-Tc0)<3°C. Actively stop the compressor and temporarily count once.

[0150] 3min, the compressor is restarted, and the phase current and other data are continuously detected in real time. At 8min, it is greater than the third preset time = 2min, the phase current = 12.2A is detected, the compressor operating frequency F = 100Hz, the indoor coil temperature Tc = 35℃, and the compressor runs until 10min, which is equal to the eighth preset time t5 = 10min, and no overcurrent shutdown fault is detected. The temporary count 1 is cleared to 0, and the stop valve is no longer judged as not open.

[0151] According to the air conditioner of some embodiments of the present application, when the air conditioner is powered on for the first time and the heating operation is started, the outdoor ambient temperature is detected to determine whether the low-temperature stop valve detection condition is met. By determining whether the low-temperature stop valve detection condition is met and temporarily counting the stop valve faults, the problem of misjudgment of the stop valve not opening fault caused by the slow exhaust pressure establishment and slow change of the compressor operating parameters when the compressor is cold started for the first time due to the outdoor temperature being too low can be solved, thereby reducing missed judgments, and after the low-temperature stop valve detection condition is met, it is determined whether the stop valve detection condition is met, and when the above detection conditions are all met, the stop valve faults are counted until the stop valve fault count and the stop valve fault temporary count reach a preset number of times, and it is determined that the stop valve has a non-opening fault. When determining whether the stop valve detection condition is met, since when the stop valve has a non-opening fault, there is a difference between the operating parameters of the air conditioner and the operating parameters when the indoor motor is blocked or the power supply voltage is extremely low, by detecting whether the stop valve detection condition is met, it is possible to avoid misjudgment of the fault caused by the compressor shutdown due to usage scenarios such as indoor motor blocking or extremely low power supply voltage, thereby improving the accuracy of the stop valve not opening fault and reducing user complaints caused by misjudgment.

[0152] The following describes a method for detecting a stop valve failure of an air conditioner according to some embodiments of the present application.

[0153] like Fig. 9 As shown, the stop valve fault detection method for an air conditioner in some embodiments of the present application at least includes: step S21-step S27.

[0154] Step S21, when the air conditioner is powered on for the first time and starts heating operation, the outdoor ambient temperature and the indoor initial coil temperature at the time of compressor startup are obtained.

[0155] Step S22: When the outdoor ambient temperature does not exceed the preset temperature threshold, determine whether the low-temperature stop valve detection condition is met.

[0156] Step S23: If the low-temperature stop valve detection condition is met, the compressor is controlled to shut down, and the stop valve failure is temporarily counted.

[0157] Step S24: after a first preset time, determine whether the stop valve detection condition is met.

[0158] Step S25, when the stop valve detection condition is met, determine that the stop valve fault temporary count is valid, and count the stop valve times, and when the stop valve temporary count and the stop valve fault count meet the preset times, determine that the stop valve is faulty.

[0159] Step S26, controlling the compressor to continue running.

[0160] Step S27, determining that the temporary stop valve fault count is invalid, and determining again that the stop valve detection condition is met.

[0161] According to the stop valve fault detection method of the air conditioner in some embodiments of the present application, when the air conditioner is powered on for the first time and the heating operation is started, the outdoor ambient temperature is detected to determine whether the low-temperature stop valve detection condition is met. By determining whether the low-temperature stop valve detection condition is met, the stop valve faults are temporarily counted, which can solve the problem of misjudgment of the stop valve failure to open due to the slow exhaust pressure establishment and slow change of the compressor operating parameters when the compressor is cold started for the first time due to the outdoor temperature being too low, thereby reducing missed judgments, and after the low-temperature stop valve detection condition is met, it is determined whether the stop valve detection condition is met, and when the above detection conditions are all met, the stop valve faults are counted until the stop valve fault count and the stop valve fault temporary count reach a preset number of times, it is determined that the stop valve has a failure to open. When determining whether the stop valve detection condition is met, since when the stop valve has a failure to open, the operating parameters of the air conditioner are different from the operating parameters when the indoor motor is blocked or the power supply voltage is extremely low, by detecting whether the stop valve detection condition is met, it is possible to avoid misjudgment of the fault caused by the compressor shutdown due to the use scenarios such as indoor motor blocking or extremely low power supply voltage, thereby improving the accuracy of the stop valve failure to open while reducing user complaints caused by misjudgment.

[0162] In some embodiments, Fig.10 , which is a schematic diagram of changes in operating parameters of the air conditioner when the stop valve is not opened in some embodiments of the present application.

[0163] like Fig.10 (a) is a schematic diagram of the curve change of indoor coil temperature and outdoor coil temperature when the stop valve is closed in some embodiments of the present application. When all the stop valves are closed, the refrigerant is compressed between the compressor exhaust port and the rough stop valve, and no refrigerant flows through the test indoor heat exchanger, while the refrigerant in the outdoor heat exchanger is quickly extracted. The indoor coil temperature, indoor ambient temperature and outdoor ambient temperature are laboratory temperatures, which theoretically remain unchanged. The outdoor coil temperature first drops rapidly and slightly, then rises slowly, and finally the outdoor coil temperature tends to the outdoor ambient temperature and is finally the same as the outdoor ambient temperature.

[0164] like Fig.10(b) is a schematic diagram of the curve structure of the exhaust pressure and the suction pressure in the closed state of the stop valve in some embodiments of the present application. When the air conditioner is in heating operation, all the stop valves are closed. Due to the abnormality of the air conditioner, the exhaust pressure of the compressor rises sharply, and the pressure difference between the suction pressure and the exhaust pressure increases sharply. Among them, the exhaust pressure rises sharply, and the maximum value before the protection shutdown far exceeds the maximum exhaust pressure Pdmax. The suction pressure drops sharply until it drops to 0 atmospheric pressure and stabilizes at 0 atmospheric pressure. At this time, it is equivalent to the outdoor heat exchanger side being in a vacuum state. If the fine stop valve is not sealed tightly or leaks slightly, it is easy to draw in air, further increasing the danger. At this time, 0 atmospheric pressure is significantly lower than the minimum suction pressure Psmin.

[0165] like Fig.10 (c) is a schematic diagram of the curve change of phase current when the stop valve is closed in some embodiments of the present application. When the pressure difference between the suction pressure and the exhaust pressure of the compressor increases sharply, the load of the compressor motor increases sharply, causing the compressor phase current to rise sharply, thereby greatly exceeding the maximum phase current value Imax specified by the air conditioner. At the same time, the increased exhaust pressure and pressure difference are very likely to exceed the use requirements of the compressor, or exceed the use requirements of the controller, resulting in a rapid overcurrent protection fault and shutdown.

[0166] Depend on Fig.10 It can be seen that when the stop valve is not opened and the air conditioner is running in heating mode, since the stop valve is closed, no refrigerant flows through the indoor heat exchanger, the indoor coil temperature will not change significantly, and the pressure difference between the exhaust pressure and the suction pressure of the compressor increases sharply, which makes the load of the compressor motor increase sharply, causing the operating parameters of the compressor, such as the phase current of the compressor, to increase sharply, greatly exceeding the maximum phase current value Imax specified by the whole machine platform. At the same time, the increased exhaust pressure and pressure difference are very likely to exceed the use requirements of the compressor or the use requirements of the controller, causing a rapid overcurrent protection fault report and shutdown. It can be understood that when the stop valve is not opened, the indoor coil temperature, the operating parameters of the compressor and the operating status of the compressor will change significantly. Therefore, when detecting whether the stop valve has a failure of not opening, the indoor coil temperature, the operating parameters of the compressor and the operating status of the compressor are detected, and when the above parameter changes meet the parameter change law when the stop valve is not opened, it is determined whether the cause of the parameter abnormality is that the stop valve is not opened.

[0167] Some embodiments of the present application obtain the operating parameters of multiple compressors and multiple indoor coil temperatures, and detect the operating parameters of the compressors and the indoor coil temperatures to determine whether the stop valve has a fault. When the stop valve fails to open, the operating parameters of the compressor and the indoor coil temperatures have a specific change pattern. By detecting whether the operating parameters of multiple compressors and multiple indoor coil temperatures meet preset conditions, it is possible to accurately determine whether the stop valve has a failure to open, thereby avoiding missed judgments and misjudgments caused by indoor motor jams, indoor motor failure shutdowns, or overcurrent protection shutdowns due to ultra-low voltage of the user's power supply, thereby improving the accuracy of the judgment of the stop valve failure to open and avoiding user complaints caused by misjudgments.

[0168] like Figure 6 As shown, the air conditioner 1 of some embodiments of the present application includes: a refrigerant circulation loop 11, an outdoor heat exchanger 12, an indoor heat exchanger 13, an indoor coil temperature sensor 14, an outdoor unit 15, an outdoor unit casing 16, a compressor 17, a stop valve 18 and a controller 19, wherein:

[0169] The refrigerant circulation loop 11 allows the refrigerant to circulate in the circulation loop through the compressor 17, the condenser, the expansion valve and the evaporator; the outdoor heat exchanger 12 and the indoor heat exchanger 13, wherein one works for the condenser and the other works for the evaporator; the indoor coil temperature sensor 14 is used to detect the indoor coil temperature; the outdoor unit 15 includes: an outdoor housing 16; a compressor 17; the outdoor heat exchanger 12 and a stop valve 18, wherein the compressor 17 is arranged in the outdoor housing 16, and is used to compress the low-temperature and low-pressure refrigerant gas into a high-temperature and high-pressure refrigerant gas and discharge it to the condenser; the stop valve 18 is arranged in the outdoor unit casing 16, and is used for opening or closing the refrigerant circulation loop 11; the controller 19 is used for determining the operating parameters of N compressors 17 and the indoor coil temperatures of N indoor heat exchangers 13 when the power is turned on for the first time and the air conditioner is turned on for heating operation. Since the operating parameters of the compressor 17 will increase sharply, and the increase of its operating parameters presents a relatively obvious increasing trend, and at the same time, since the shut-off valve 18 fails to open, no refrigerant flows through the indoor heat exchanger 13, and the indoor coil temperature remains basically unchanged, therefore, the temperatures of multiple indoor coils are detected.

[0170] When the operating parameters of N compressors and the indoor coil temperatures of N indoor heat exchangers meet the preset conditions, the compressors are controlled to stop. After the first low temperature preset time, the operating parameters of the N compressors and the indoor coil temperatures of the N indoor heat exchangers are determined again. When the operating parameters of the N compressors and the indoor coil temperatures of the N indoor heat exchangers meet the preset conditions for a preset number of times, a stop valve failure is determined, and the compressors are controlled to stop, so as to realize stop valve fault detection.

[0171] In some embodiments, when the controller is powered on for the first time and the air conditioner is operated in the heating mode, the indoor ambient temperature and the indoor coil temperature at the time of compressor startup are detected and stored. At this time, the operating parameters of N compressors and the indoor coil temperatures of N indoor heat exchangers are determined, and the operating parameters of the N compressors and the indoor coil temperatures of the N indoor heat exchangers are detected to determine whether the operating parameters of the N compressors and the indoor coil temperatures of the N indoor heat exchangers meet the preset conditions. When the above parameters meet the preset conditions, it is determined that the stop valve may not be opened, and the compressor is controlled to stop. At this time, the number of times the operating parameters of the compressor and the indoor coil temperature of the indoor heat exchanger meet the preset conditions is counted. For example, the number of times the operating parameters of the compressor and the indoor coil temperature meet the preset conditions is counted as 1.

[0172] After the compressor is controlled to stop, after the first low temperature preset time reaches, for example, 3 minutes, the compressor is restarted, and the operating parameters of the N compressors and the indoor coil temperatures of the N indoor heat exchangers are determined again, and the phase currents of the N compressors and the indoor coil temperatures of the N indoor heat exchangers are analyzed again, and when the phase currents of the compressors and the indoor coil temperatures meet the preset conditions, it is determined that the stop valve may not be opened, and the compressor is controlled to stop. At this time, the number of times the compressor operating parameters and the indoor coil temperature meet the preset conditions is counted as 1 again, until the compressor operating parameters and the indoor coil temperature meet the preset conditions for a preset number of times, for example, when they meet twice, it is determined that the stop valve is not opened. When the air conditioner is turned on for heating operation, the operating parameters of the N compressors and the indoor coil temperatures of the N indoor heat exchangers are analyzed, and when the compressor operating parameters and the indoor coil temperature meet the preset conditions for a preset number of times, it is determined that the stop valve is not opened.

[0173] It is understandable that when the stop valve is not opened, the changes in the indoor coil temperature and the operating parameters of the compressor are significantly different from the changes in the indoor coil temperature and the operating parameters of the compressor when the indoor motor is blocked or shut down due to a fault and the AC power supply voltage is extremely low. Therefore, by detecting the indoor coil temperature and the operating parameters of the compressor, the stop valve failure can be quickly and accurately determined, and when the operating parameters of the compressor and the indoor coil temperature of the indoor heat exchanger meet the preset conditions, the compressor is controlled to shut down without waiting for the overcurrent protection to shut down, which can make the protection timing earlier.

[0174] For example, taking the operating parameter of the compressor as the phase current of the compressor, when the outdoor controller is powered on for the first time and the heating is in operation, the phase currents of N compressors and the indoor coil temperatures of N indoor heat exchangers are determined, and the phase currents of the N compressors are respectively recorded as I(1), I(2), ...I(n-1), I(n), and the indoor coil temperatures of the N indoor heat exchangers are, for example, recorded as Tc(1), Tc(2), ...Tc (n-1), Tc (n). At this time, it is determined whether the phase current of the compressor and the indoor coil temperature of the indoor heat exchanger meet the preset conditions. When the phase current of the compressor and the indoor coil temperature of the indoor heat exchanger meet the preset conditions, it is determined that the stop valve may not be opened, and the compressor is actively controlled to stop, and the number of times the phase current of the compressor and the indoor coil temperature of the indoor heat exchanger meet the preset conditions is counted as 1.

[0175] After the compressor is controlled to stop, after the first low temperature preset time, for example 3 minutes, the phase current of the compressor and the indoor coil temperature of the indoor heat exchanger are detected again, and when the phase current of the compressor and the indoor coil temperature of the indoor heat exchanger meet the preset conditions for the preset number of times, it is determined that the stop valve is not opened.

[0176] According to the air conditioner of some embodiments of the present application, when the air conditioner is powered on for the first time and the heating operation is started, the operating parameters of N compressors and N indoor coil temperatures are analyzed. When the stop valve fails to open, the operating parameters of the compressor and the indoor coil temperature meet the preset conditions, while in other faults, such as the indoor AC motor is blocked or shut down due to a fault and the AC power supply voltage is extremely low, the operating parameters of the compressor and the indoor coil temperature do not meet the preset conditions. Therefore, by detecting the operating parameters of the compressor and the indoor coil temperature, and when the operating parameters of the compressor and the N indoor coil temperatures meet the preset conditions for a preset number of times, it is determined that the stop valve has a failure to open, thereby avoiding misjudgment of a fault caused by the compressor shutting down due to usage scenarios such as indoor motor blocking or extremely low power supply voltage, thereby improving the accuracy of the stop valve failure to open, reducing the air conditioner locking caused by misjudgment, thereby reducing user complaints, and when the compressor operating parameters and the indoor coil temperature of the indoor heat exchanger meet the preset conditions, the compressor is controlled to shut down without waiting for the overcurrent protection shutdown, which can make the protection timing earlier.

[0177] In some embodiments, the operating parameters of N compressors and N indoor coil temperatures meet preset conditions, that is, the difference between the operating parameter value of the compressor at a later moment and the operating parameter of the compressor at a previous moment is a positive value, and the difference is greater than the second preset parameter threshold, and the operating parameter of the compressor is greater than the first preset parameter threshold, and the temperature difference between the indoor coil temperature and the indoor initial coil temperature does not exceed the third preset parameter threshold, it is considered that the operating parameters of the compressor and the indoor coil temperature meet the preset conditions.

[0178] Specifically, by calculating the difference between the operating parameter value of the compressor at a later moment and the operating parameter of the compressor at a previous moment, the difference between the operating parameters of N-1 compressors is obtained, and the temperature difference between N indoor coil temperatures and the indoor initial coil temperature is calculated to obtain the temperature difference of N compressors; and when the difference between the operating parameter of the compressor at a later moment and the operating parameter of the compressor at a previous moment is positive, and the operating parameters of the compressor are greater than the first preset parameter threshold, and the difference between the N-1 operating parameters exceeds the second preset parameter threshold, and the N temperature differences do not exceed the third preset parameter threshold, it is determined that the compressor operating parameter value and the coil temperature meet the preset conditions, and by judging whether the operating parameters and the coil temperature of the compressor meet the preset conditions, it can be accurately judged whether there is a stop valve failure that is not opened.

[0179] In some embodiments, when determining whether the compressor operating parameters and the indoor coil temperature meet the preset conditions, the compressor operating parameters and the indoor coil temperature are detected.

[0180] For example, taking the operating parameter of the compressor as the phase current of the compressor, it is determined whether the phase current of the compressor and the indoor coil temperature meet the preset conditions. The phase currents of the compressor are respectively recorded as I(1), I(2), I(3)...I(n-1), and I(n). The indoor coil temperatures of the indoor heat exchanger are respectively recorded as Tc(1), Tc(2), Tc(3)...Tc(n-1), and Tc(n). At this time, the difference between the phase current of the compressor at the next moment and the phase current of the compressor at the previous moment is calculated, that is, I(n)-I(n-1), I(3)-I(2) are calculated, and I(2)-I(1) is calculated by analogy until the difference in the phase currents of N-1 compressors is obtained, and the temperature difference between the N indoor coil temperatures and the indoor initial coil temperature is calculated, that is, Tc(n)-Tc(0), Tc(n-1)-Tc(0) are calculated, and Tc(1)- Tc(0), when the operating parameters of the compressor at the next moment are greater than the operating parameters of the compressor at the previous moment, that is, the phase current of the compressor shows an increasing trend, and the operating parameters of the compressor are greater than the first preset parameter threshold, for example, I(n)>I(n-1)>I(n-2)>…>I(1), and the difference of the phase currents of the N compressors exceeds the second preset parameter threshold, and I(n)-I(n-1)>I2, I(n-1)-I(n-2)>I2, and so on, until I(2)-I(1)>I2, and the N temperature differences do not exceed the third preset parameter threshold, that is, Tc(n)-Tc(0)≤△T1, Tc(n-1)-Tc(0)≤△T1, and so on, until Tc(1)-Tc(0)≤△T1, at this time, it is determined that the operating parameters and coil temperature of the compressor meet the preset conditions, and when the preset conditions are met, the compressor is controlled to stop. By detecting the indoor coil temperature of the indoor heat exchanger and the operating parameters of the compressor, it is possible to distinguish between the failure of the stop valve to open and other shutdown conditions caused by overcurrent protection, such as indoor motor stalling, shutdown, or overcurrent protection shutdown caused by extremely low power supply voltage, effectively reducing missed judgments and misjudgments, thereby improving the accuracy of stop valve fault judgment.

[0181] In some embodiments, when determining the operating parameters of N compressors and the indoor coil temperatures of N indoor heat exchangers, within a second preset time, it is determined whether the operating parameters of the compressors are greater than a first preset parameter threshold; if so, a reference time for the compressor operation is determined; the operating parameters of the N compressors and the indoor coil temperatures of the N indoor heat exchangers are determined based on the reference time, and the time when the operating parameters of the compressors are greater than the first preset parameter is used as the reference time for the compressor operation, and the operating parameters of the compressors and the indoor coil temperatures determined at the reference time are used as the reference, and the operating parameters of the compressors and the indoor coil temperatures at the reference time are used as the reference, and the operating parameters of the compressors and the indoor coil temperatures are obtained at regular intervals until the operating parameters of the N compressors and the N indoor coil temperatures are obtained.

[0182] In some embodiments, when determining the operating parameters of N compressors and the indoor coil temperatures of N indoor heat exchangers, it is necessary to detect the phase current of the compressor within a second preset time, such as 0-t1 minutes, when the outdoor controller of the air conditioner is powered on for the first time and the heating operation is in progress. When the phase current of the compressor is greater than the first preset parameter threshold, the reference time of the compressor operation is determined. The first preset parameter threshold is, for example, recorded as I1, that is, when the phase current of the compressor is ≥I1, this moment is used as the reference time of the compressor operation, that is, the reference time 0. According to the reference time 0, the operating parameters of the N compressors and the indoor coil temperatures of the N indoor heat exchangers are determined. By judging whether the operating parameters of the compressor are greater than the second preset parameter threshold within the second preset time, the reference time of the compressor operation is determined, so that the operating parameters of the N compressors and the indoor coil temperatures of the N indoor heat exchangers are determined according to the reference time, so as to provide a basis for the fault judgment of the stop valve.

[0183] In some embodiments, when determining the operating parameters of N compressors and the indoor coil temperatures of N indoor heat exchangers according to the reference time, the operating parameters of the compressors and the indoor coil temperatures at the reference time are determined; the operating parameters of N-1 compressors and the indoor coil temperatures are obtained with the reference time as the time starting point and the third preset interval as the interval; the operating parameters of N compressors are determined according to the operating parameters of the compressors at the reference time and the operating parameters of N-1 compressors, and the indoor coil temperatures of N indoor heat exchangers are determined according to the indoor coil temperatures at the reference time and the indoor coil temperatures of N-1 indoor heat exchangers, wherein the third preset interval is less than the first low temperature preset time. The operating parameters of the compressors and the indoor coil temperatures of the indoor heat exchangers are obtained every third preset interval.

[0184] In some embodiments, after determining the reference time of the compressor, the reference time is used as the reference time 0, and the initial operating parameters and indoor coil temperature of the compressor at this time are detected. The reference time is used as the starting point, and the third preset interval time is used as the interval. The operating parameters and indoor coil temperature of the compressor are detected and obtained every third preset interval time until N-1 compressor operating parameter values ​​and N-1 indoor coil temperatures are obtained, and N compressor operating parameter values ​​are determined according to the compressor operating parameters at the reference time and the N-1 compressor operating parameter values, and the indoor coil temperatures of N indoor heat exchangers are determined according to the indoor coil temperature at the reference time and the N-1 indoor coil temperatures. By determining the reference time of the compressor, the operating parameters of N compressors and the indoor coil temperatures of N indoor heat exchangers are obtained, so that the stop valve failure can be detected according to the operating parameters of N compressors and the indoor coil temperatures of N indoor heat exchangers.

[0185] In some embodiments, when the operating parameters of N compressors and N indoor coil temperatures do not meet the preset conditions, the compressor is controlled to continue running until the continuous running time of the compressor reaches a third preset time, and the operating parameters of the compressor and the indoor coil temperature are no longer detected to see whether they meet the preset conditions, wherein the third preset time is greater than the first low temperature preset time. If the indoor coil temperature and the operating parameters of the compressor do not meet the preset conditions within the specified time, the running time of the compressor is timed. When the running time reaches the third preset time, it is considered that the stop valve detection condition is not met, and the stop valve does not have a non-opening fault.

[0186] In some embodiments, the air conditioner is turned on for heating operation, and the operating parameters of N compressors and the indoor coil temperatures of N indoor heat exchangers are judged. When the operating parameters of the compressor and the indoor coil temperatures of the indoor heat exchangers do not meet the preset conditions, the compressor is controlled to remain in the on state, and the continuous operation time of the compressor is counted until the continuous operation time of the compressor reaches a third preset time, for example, 10 minutes, and it is considered that the stop valve has not failed to open. At this time, it is no longer detected whether the operating parameters of the compressor and the indoor coil temperature meet the preset conditions, that is, it is no longer determined whether the stop valve has failed to open, and all data related to the determination of the stop valve failure is cleared. By obtaining the continuous operation time of the compressor, and when the continuous operation time of the compressor reaches the third preset time, the operating parameters of the compressor and the indoor coil temperature are no longer detected to meet the preset conditions, it is possible to avoid misjudgment of the stop valve failure caused by the external unknown environment and unknown electromagnetic interference, thereby improving the reliability of the stop valve determination.

[0187] In some embodiments, when the operating parameters of N compressors and the indoor coil temperatures of N indoor heat exchangers do not meet the preset conditions for a preset number of times, the controller is further configured to: control the compressor to continue running, and count the running time of the compressor, until the cumulative running time of the compressor reaches the fourth movement preset time, and no longer detect whether the operating parameters of the compressor and the indoor coil temperature meet the preset conditions, wherein the fourth movement preset time is greater than the third preset time, wherein, when judging whether the operating parameters of the compressor and the indoor coil temperature meet the preset conditions, it is necessary to detect the fault count of the stop valve, if the fault count of the stop valve does not reach the preset number of times, for example, when the fault count of the stop valve is 1, the compressor is controlled to stop, but when judging again whether the preset conditions are met, it is detected that the operating parameters of the compressor and the indoor coil temperature do not meet the preset conditions, then the running time of the compressor is counted, and when the cumulative running time of the compressor reaches the fourth movement preset time, it is considered that the preset conditions are not met, and the stop valve does not have a non-opening fault.

[0188] In some embodiments, when the operating parameters of N compressors and the indoor coil temperatures of N indoor heat exchangers do not meet the preset conditions for a preset number of times, the compressor is controlled to continue running, and the running time of the compressor is counted until the cumulative running time of the compressor reaches a fourth movement preset time, for example, 30 minutes, and the operating parameters of the compressor and the indoor coil temperature are no longer detected to see whether they meet the preset conditions. By obtaining the cumulative running time of the compressor and when the cumulative running time of the compressor reaches the fourth movement preset time, the operating parameters of the compressor and the indoor coil temperature are no longer detected to see whether they meet the preset conditions, it is possible to avoid misjudgment of stop valve failures caused by unknown external environments and unknown electromagnetic interference, thereby improving the reliability of stop valve determination.

[0189] It is understandable that, under normal circumstances, the stop valve failure to open may only occur once. When the air conditioner is not in use, the user will actively cut off the power to the air conditioner, or even if the indoor unit is powered on, when it is not turned on, the indoor controller will automatically cut off the power to the outdoor controller. Once the outdoor controller is powered off, the operating parameters of the compressor, the indoor coil temperature of the indoor heat exchanger, and the data of the air conditioner's execution of the stop valve protection strategy will all be lost. Therefore, each time the outdoor controller is powered on again, a detection and judgment process for the stop valve failure to open will be performed.

[0190] In some embodiments, when the operating parameters of N compressors and the indoor coil temperatures of N indoor heat exchangers meet preset conditions for a preset number of times, after the compressor is controlled to stop, an alarm message of a stop valve failure is issued, and the compressor is controlled to stop and no longer start automatically.

[0191] In some embodiments, when the operating parameters of the compressor and the indoor coil temperature meet the preset conditions for a preset number of times, that is, the operating parameters of the compressor at a later moment are greater than the operating parameters of the compressor at a previous moment, and the differences of the N-1 operating parameter values ​​exceed the second preset parameter threshold, and the number of times that the N temperature differences do not exceed the third preset parameter threshold meets the preset number of times, for example, twice, at this time, it is determined that the stop valve is not open, and an alarm message of a stop valve failure is issued, and the compressor is controlled not to start automatically.

[0192] In some embodiments, the operating parameters of the compressor include: any one of the effective value of the compressor, the input power of the compressor, the whole machine input power of the air conditioner, and the whole machine input current of the air conditioner.

[0193] In some embodiments, the operating parameters of the compressor can be any one of the effective value of the compressor, the compressor input power, the whole machine input power of the air conditioner and the whole machine input current of the air conditioner. It can be understood that when the air conditioner is running in heating mode, the stop valve is closed and the refrigerant is compressed in a very small space, causing the exhaust pressure to rise sharply and the suction pressure to drop sharply, so that the suction and exhaust pressure difference increases sharply, and then causes the system load to increase sharply, and act on the compressor drive control. In the drive control of the compressor, the increase in load may cause the compressor input power to increase, the compressor phase current to increase at the same voltage, the whole machine input power to increase, the whole machine input current to increase at the same voltage, etc. Therefore, any one of the above can be selected as the operating parameter of the compressor.

[0194] At present, the compressor uses a permanent magnet synchronous motor. The general FOC algorithm needs to transform the coordinate of the current to convert the compressor phase current in the rotating coordinate system into the D-axis and Q-axis currents in the stationary coordinate system, and control the D-axis and Q-axis currents. When the phase current of the compressor increases, the corresponding D-axis current and Q-axis current also increase accordingly. The essence of the FOC algorithm is to combine the three-way current vectors and then decompose them into two components that are perpendicular and parallel to the stationary coordinate system. The D-axis current and Q-axis current can be obtained by calculating and transforming the phase current in the rotating coordinate system through a function, that is, the D-axis current and Q-axis current are the currents after the phase current has undergone coordinate transformation. Therefore, the D-axis current, the Q-axis current or a combination of the D-axis and the Q-axis is used to determine the operating parameters of the compressor.

[0195] The phase current of the compressor is usually a sine wave. There are two descriptions of the magnitude of the sine wave current value: one is the effective value of the current and the other is the peak value of the current. The effective value of the phase current is the root mean square value of the current, and the peak value of the phase current is the instantaneous maximum value of the current within a certain period of time. When the controller controls according to the detected current value, it will always detect the instantaneous value of the phase current and compare it to obtain the instantaneous maximum value of the current within a certain time period, that is, the phase current peak value; it will also perform root mean square calculation based on the peak value to obtain the operating parameter value of the compressor.

[0196] For example, within the first preset time, such as 40 seconds, it is detected that the phase current of the compressor exceeds the first preset parameter threshold, such as exceeding 12A, then the phase current of the compressor continues to be detected; it is also possible to detect that the input power of the compressor exceeds the first preset parameter threshold, such as exceeding 4.2W at 40 seconds, then the input power of the compressor continues to be detected; it is also possible to detect that the whole input power of the air conditioner exceeds the first preset parameter threshold, such as exceeding 4.3W at 40 seconds, then the whole input power of the air conditioner continues to be detected; it is also possible to detect that the whole input current of the air conditioner exceeds the first preset parameter threshold, such as exceeding 18A at 40 seconds, then the whole input current of the air conditioner continues to be detected; it is also possible to detect that the Q-axis current of the compressor exceeds the first preset parameter threshold, such as exceeding 10A at 40 seconds, then the Q-axis current of the compressor continues to be detected.

[0197] The following is an example of the fault detection of the stop valve, and the parameters of the air conditioner are set as follows.

[0198] The third preset interval time interval is recorded as △t, △t=1 second, the third preset time is recorded as t2, t2=10min, the fourth movement preset time is recorded as t3, t3=30 min, the third preset parameter threshold is recorded as △T1, △T1=3℃, the first preset parameter threshold is recorded as I1, I1=12V, the second preset parameter threshold is recorded as I2, I2=1A, the preset number of times is recorded as i, i=2, and the above parameters can be set as needed.

[0199] In some embodiments, when the outdoor unit of the air conditioner is powered on for the first time, the heating operation mode is turned on, and the compressor is started. At this time, the controller detects the indoor ambient temperature and indoor coil temperature at the time of compressor startup, the indoor ambient temperature Tin0=20°C, the indoor coil temperature Tc0=21°C of the indoor heat exchanger, the outdoor ambient temperature Tout0=15°C, the outdoor coil temperature Te0=15°C, and the exhaust temperature Td0=15°C. The phase current of the compressor is also detected in real time.

[0200] During the set time period, for example, at 40 seconds, the phase current of the compressor is detected to be 12A, which is equal to the fourth preset parameter threshold I1=12A, denoted as I(1)=12A, and the indoor coil temperature is 21°C, denoted as Tc(1)=21°C. After 1 second, the phase current and indoor coil temperature are detected and recorded as I(2)=13.2A>12A, Tc(2)= 21℃; after another 1 second, the phase current and indoor coil temperature are detected and recorded as I(3)=14.6A>12A, Tc(3)= 21℃; after another 1 second, the phase current and indoor coil temperature are detected and recorded as I(4)=15.8A>12A, Tc(4)= 21℃; I(4)- I(3)=1.2A>1A, I(3)- I(2)=1.4A>1A, I(2)- I(1) =1.2A>1A and Tc (4)- Tc 0=21-21=0℃<3℃, Tc (3)- Tc 0=21-21=0℃<3℃, Tc (2)- Tc 0=21-21=0℃<3℃, Tc (1)- Tc 0=21-21=0℃<3℃. If the above preset conditions are met, there may be a stop valve failure. The compressor is controlled to stop and counted once.

[0201] 3min later, the compressor is restarted and the phase current and other data are continuously detected in real time. If at 28s, the phase current is detected to be 12A, which is equal to the first preset parameter threshold I1, recorded as I(1)=12A, and the indoor coil temperature is 21℃, recorded as Tc(1)=21℃. After 1 second, the phase current and the indoor coil temperature of the indoor heat exchanger are detected and recorded as I(2)=13.2A>12A, Tc(2)= 21℃; after another 1 second, the phase current and the indoor coil temperature of the indoor heat exchanger are detected and recorded as I(3)=14.6A>12A, Tc(3)= 21℃; after another 1 second, the phase current and the indoor coil temperature of the indoor heat exchanger are detected and recorded as I(4)=15.8A>12A, Tc(4)= 21℃; I(4)- I(3)=1.2A>1A, I(3)- I(2) =1.4A>1A, I(2)- I(1)=1.2A>1A and Tc (4)- Tc 0=21-21=0℃<3℃, Tc (3)- Tc 0=21-21=0℃<3℃, Tc (2)-Tc 0=21-21=0℃<3℃, Tc (1)- Tc 0=21-21=0℃<3℃, if the above preset conditions are met, it may be a stop valve failure, and the compressor will be stopped automatically. Count 1 time.

[0202] When the operating parameters of the compressor and the indoor coil temperature meet the preset conditions for a preset number of times, for example, twice, a stop valve failure is reported, and the compressor is no longer controlled to start automatically.

[0203] In some embodiments, the outdoor unit of the air conditioner is powered on for the first time, the heating operation mode is turned on, the compressor is started, and the controller detects the indoor ambient temperature Tin0 = 20°C, the indoor coil temperature Tc0 = 21°C, the outdoor ambient temperature Tout0 = 15°C, the outdoor coil temperature Te0 = 15°C, and the exhaust temperature Td0 = 15°C at the start time. The phase current of the compressor is detected in real time.

[0204] If at 59 seconds, the phase current is detected to be 12A, which is equal to the first preset parameter threshold I1=12A, recorded as I(1)=12A, and the indoor coil temperature is 45°C, recorded as Tc(1)=35°C. After 1 second, the phase current and the indoor coil temperature of the indoor heat exchanger are detected and recorded as I(2)=12.2A>12A, Tc(2)= 46℃; after another 1 second, the phase current and the indoor coil temperature of the indoor heat exchanger are detected and recorded as I(3)=12.4A>12A, Tc(3)= 47℃; after another 1 second, the phase current and the indoor coil temperature are detected and recorded as I(4)=12.2A>12A, Tc(4)= 48℃; I(4)- I(3)=0.2A<1A, I(3)- I(2) =0.2A<1A, I(2)- I(1) =-0.2A<1A and Tc (4)- Tc 0=48-21=27℃>3℃, Tc (3)- Tc 0=47-21=26℃>3℃, Tc (2)- Tc 0=46-21=25℃>3℃, Tc (1)- Tc 0=45-21=24℃>3℃, the above preset conditions are not met and the compressor continues to operate.

[0205] The compressor runs until 10 minutes, which is equal to the fourth movement preset time t3=10 minutes, and there is no abnormality. Then, the stop valve failure will no longer be judged.

[0206] According to the air conditioner of some embodiments of the present application, when the air conditioner is powered on for the first time and the heating operation is started, the operating parameters of N compressors and N indoor coil temperatures are analyzed. When the stop valve fails to open, the operating parameters of the compressor and the indoor coil temperature meet the preset conditions, while in other faults, such as the indoor AC motor is blocked or shut down due to a fault and the AC power supply voltage is extremely low, the operating parameters of the compressor and the indoor coil temperature do not meet the preset conditions. Therefore, by detecting the operating parameters of the compressor and the indoor coil temperature, and when the operating parameters of the compressor and the N indoor coil temperatures meet the preset conditions for a preset number of times, it is determined that the stop valve has a failure to open, thereby avoiding misjudgment of a fault caused by the compressor shutting down due to usage scenarios such as indoor motor blocking or extremely low power supply voltage, thereby improving the accuracy of the stop valve failure to open, reducing the air conditioner locking caused by misjudgment, thereby reducing user complaints, and when the compressor operating parameters and the indoor coil temperature of the indoor heat exchanger meet the preset conditions, the compressor is controlled to shut down without waiting for the overcurrent protection shutdown, which can make the protection timing earlier.

[0207] The following is an illustration of the air conditioner stop valve fault detection method according to some embodiments of the present application.

[0208] like Fig.11 As shown, the air conditioner stop valve fault detection method of some embodiments of the present application at least includes steps S31 to S3.

[0209] Step S31, when the air conditioner is powered on for the first time and starts heating operation, the operating parameters of N compressors and the indoor coil temperatures of N indoor heat exchangers are determined.

[0210] In some embodiments, when the controller is powered on for the first time and the air conditioner operates in heating mode, the indoor ambient temperature and indoor coil temperature at the time of compressor startup are detected and stored. At this time, the operating parameters of N compressors and the indoor coil temperatures of N indoor heat exchangers are determined.

[0211] Step S32, determining whether the operating parameters of the N compressors and the temperatures of the N indoor coils meet preset conditions.

[0212] Step S33, if the operating parameters of the N compressors and the N indoor coil temperatures meet the preset conditions, the compressors are controlled to stop, and after the first low temperature preset time, the operating parameters of the N compressors and the indoor coil temperatures of the N indoor heat exchangers are determined again.

[0213] Step S34, determining whether the operating parameters of the N compressors and the temperatures of the indoor coils of the N indoor heat exchangers meet the preset conditions for a preset number of times.

[0214] Step S35: When the preset conditions are met for the preset number of times, it is determined that the stop valve is faulty and the compressor is controlled to shut down.

[0215] Step S36, controlling the compressor to continue running.

[0216] Step S37, detecting the running time of the compressor, and when the running time of the compressor reaches the fourth movement preset time, no longer detecting whether the preset condition is met.

[0217] According to the air conditioner of some embodiments of the present application, when the air conditioner is powered on for the first time and the heating operation is started, the operating parameters of N compressors and N indoor coil temperatures are analyzed. When the stop valve fails to open, the operating parameters of the compressor and the indoor coil temperature meet the preset conditions, while in other faults, such as the indoor AC motor is blocked or shut down due to a fault and the AC power supply voltage is extremely low, the operating parameters of the compressor and the indoor coil temperature do not meet the preset conditions. Therefore, by detecting the operating parameters of the compressor and the indoor coil temperature, and when the operating parameters of the compressor and the N indoor coil temperatures meet the preset conditions for a preset number of times, it is determined that the stop valve has a failure to open, thereby avoiding misjudgment of a fault caused by the compressor shutting down due to usage scenarios such as indoor motor blocking or extremely low power supply voltage, thereby improving the accuracy of the stop valve failure to open, reducing the air conditioner locking caused by misjudgment, thereby reducing user complaints, and when the compressor operating parameters and the indoor coil temperature of the indoor heat exchanger meet the preset conditions, the compressor is controlled to shut down without waiting for the overcurrent protection shutdown, which can make the protection timing earlier.

[0218] In some embodiments, when the operating parameters of N compressors and N indoor coil temperatures meet preset conditions, it includes: calculating the difference between the operating parameter value of the compressor at a later moment and the operating parameter of the compressor at a previous moment to obtain the difference between the operating parameters of N-1 compressors, and calculating the temperature difference between N indoor coil temperatures and the indoor initial coil temperature to obtain the temperature difference of N compressors; when the operating parameters of the compressor at a later moment are all greater than the operating parameters of the compressor at the previous moment, and are all greater than the first preset parameter threshold, and the differences of N-1 operating parameters all exceed the second preset parameter threshold, and the N temperature differences do not exceed the third preset parameter threshold, it is determined that the compressor operating parameter values ​​and the coil temperature meet the preset conditions.

[0219] In some embodiments, when determining whether the compressor operating parameters and the indoor coil temperature meet the preset conditions, the compressor operating parameters and the indoor coil temperature are detected.

[0220] For example, taking the compressor operating parameter as the compressor phase current as an example, determine whether the compressor phase current and the indoor coil temperature meet the preset conditions. The compressor phase currents are recorded as I(1), I(2), I(3)...I(n-1), I(n), and the indoor coil temperatures of the indoor heat exchanger are recorded as Tc(1), Tc(2), Tc(3)...Tc(n-1), Tc(n). At this time, calculate the difference between the compressor phase current at the next moment and the compressor phase current at the previous moment, that is, calculate I(n)-I(n-1), I(3)-I(2), and so on to calculate I(2)-I(1), until the difference in the phase currents of N-1 compressors is obtained, and calculate the temperature difference between the N indoor coil temperatures and the indoor initial coil temperature, that is, calculate Tc(n)-Tc(0), Tc(n-1)-Tc(0), and so on to calculate Tc(1)- Tc(0), when the operating parameters of the compressor at the next moment are greater than the operating parameters of the compressor at the previous moment, that is, the phase current of the compressor shows an increasing trend, and the operating parameters of the compressor are greater than the first preset parameter threshold, for example, I(n)>I(n-1)>I(n-2)>…>I(1), and the difference of the phase currents of the N compressors exceeds the second preset parameter threshold, and I(n)-I(n-1)>I2, I(n-1)-I(n-2)>I2, and so on, until I(2)-I(1)>I2, and the N temperature differences do not exceed the third preset parameter threshold, that is, Tc(n)-Tc(0)≤△T1, Tc(n-1)-Tc(0)≤△T1, and so on, until Tc(1)-Tc(0)≤△T1, at this time, it is determined that the operating parameters and coil temperature of the compressor meet the preset conditions, and when the preset conditions are met, the compressor is controlled to stop. By detecting the indoor coil temperature of the indoor heat exchanger and the operating parameters of the compressor, it is possible to distinguish between the failure of the stop valve to open and other shutdown conditions caused by overcurrent protection, such as indoor motor stalling, shutdown, or overcurrent protection shutdown caused by extremely low power supply voltage, effectively reducing missed judgments and misjudgments, thereby improving the accuracy of stop valve fault judgment.

[0221] In some embodiments, by obtaining the operating parameters of the compressor and the peak value of the phase current of the compressor, and detecting the operating parameters of the compressor and the peak current of the compressor, it is determined whether the stop valve has a fault. Since when the stop valve fails to open, the operating parameters of the compressor and the peak value of the phase current of the compressor have a specific change pattern, by detecting whether the operating parameters of multiple compressors and the peak values ​​of the phase current of the compressor meet the preset conditions, it is possible to accurately determine whether the stop valve has a failure to open, thereby avoiding missed judgments and misjudgments caused by indoor motor jams, indoor motor failure shutdowns, or overcurrent protection shutdowns due to ultra-low voltage of the user power supply, thereby improving the accuracy of the judgment of the stop valve failure to open and avoiding user complaints caused by misjudgments.

[0222] like Figure 6 As shown, the air conditioner 1 of some embodiments of the present application includes: a refrigerant circulation loop 11, an outdoor heat exchanger 12, an indoor heat exchanger 13, an indoor coil temperature sensor 14, an outdoor unit 15, an outdoor unit casing 16, a compressor 17, a stop valve 18 and a controller 19, wherein:

[0223] The refrigerant circulation loop 11 allows the refrigerant to circulate in the circulation loop through the compressor 17, the condenser, the expansion valve and the evaporator; the outdoor heat exchanger 12 and the indoor heat exchanger 13, wherein one works for the condenser and the other works for the evaporator; the indoor coil temperature sensor 14 is used to detect the indoor coil temperature; the outdoor unit 15 includes: an outdoor housing 16; a compressor 17; the outdoor heat exchanger 12 and a stop valve 18, wherein the compressor 17 is arranged in the outdoor housing 16, and is used to compress the low-temperature and low-pressure refrigerant gas into a high-temperature and high-pressure refrigerant gas and discharge it to the condenser; the stop valve 18 is arranged in the outdoor unit housing 16, and is used to open or close the refrigerant circulation loop 11; when the controller 19 is powered on for the first time and the air conditioner is turned on for heating operation, the operating parameters of N compressors 17 and the phase current peak value of the compressor 17 are determined. When the stop valve 18 fails to open, the current peak value of the compressor 17 increases rapidly, and the operating parameters of the compressor 17 conform to a specific rule.

[0224] When the operating parameters of N compressors and the peak value of the phase current of the compressors meet the preset conditions, it is considered that the stop valve may not be opened. At this time, the compressor is controlled to stop and count is performed. After the first low temperature preset time, the operating parameters of the N compressors and the peak value of the phase current of the compressors are determined again. When the operating parameters of the compressors and the peak value of the current of the compressors meet the preset conditions for a preset number of times, for example, when the preset conditions are met twice, it is determined that the stop valve is faulty and the compressor is controlled to stop.

[0225] In some embodiments, when the controller is powered on for the first time and the air conditioner is operating in heating mode, the operating parameters of N compressors and the phase current peak values ​​of the compressors are determined, and the operating parameters of the N compressors and the phase current peak values ​​of the compressors are detected to determine whether the operating parameters of the N compressors and the phase current peak values ​​of the compressors meet preset conditions. When the above parameters meet the preset conditions, it is determined that the stop valve may not be opened, and the compressor is controlled to stop. At this time, the number of times the operating parameters of the compressors and the current peak values ​​of the compressors meet the preset conditions is counted.

[0226] After controlling the compressor to stop, the compressor is restarted after the first low temperature preset time, for example, 3 minutes later, and the operating parameters of the N compressors and the phase current peak values ​​of the compressors are determined again, and the operating parameters of the N compressors and the phase current peak values ​​of the compressors are detected again to determine whether the operating parameters of the N compressors and the phase current peak values ​​of the compressors meet the preset conditions, and when the operating parameters of the compressors and the current peak values ​​of the compressors meet the preset conditions for a preset number of times, for example, when the operating parameters of the compressors and the current peak values ​​of the compressors meet the preset conditions twice, it is determined that the stop valve is not opened, so that the stop valve failure to open can be quickly and accurately determined, and when the operating parameters of the compressors and the phase current peak values ​​of the compressors meet the preset conditions, the compressor is controlled to stop without waiting for the overcurrent protection to shut down, which can make the protection timing earlier.

[0227] For example, taking the compressor operating parameter as the compressor phase current, when the outdoor controller is powered on for the first time and the heating is in operation, the phase currents of N compressors and the current peaks of the compressors are determined, and the phase currents of the N compressors are respectively recorded as I(1), I(2), ...I(n-1), I(n). At this time, it is determined whether the phase current of the compressor and the current peak of the compressor meet the preset conditions. When the phase current of the compressor and the current peak of the compressor meet the preset conditions, it is determined that the stop valve may not be opened, and the compressor is actively controlled to stop, and the number of times the phase current of the compressor and the current peak of the compressor meet the preset conditions is counted as 1.

[0228] After controlling the compressor to stop, after the first low temperature preset time, for example 3 minutes, the phase current of the compressor and the current peak of the compressor are detected again, and when the phase current of the compressor and the current peak of the compressor meet the preset conditions for the preset number of times, it is determined that the stop valve is not open.

[0229] It can be understood that the operating parameters of the compressor can be any one of the phase current of the compressor, the input power of the compressor, the whole input power of the air conditioner and the whole input current of the air conditioner. The phase current of the compressor is usually a sine wave. There are two descriptions about the size of the sine wave: one is the effective value of the current, and the other is the current peak. The effective value of the phase current is the root mean square value of the current, and the phase current peak is the instantaneous maximum value of the current within a certain period of time. A conventional controller will always detect the instantaneous value of the phase current and compare it to obtain the maximum value of the current within a certain time period, that is, the phase current peak value; it will also perform root mean square calculation based on the peak value to obtain the effective value of the phase current.

[0230] According to the air conditioner of some embodiments of the present application, when the air conditioner is powered on for the first time and the heating operation is started, the operating parameters of N compressors and the phase current peak values ​​of the compressors are analyzed. Since the operating parameters of the compressors and the phase current peak values ​​of the compressors meet a specific rule when the stop valve is not opened, the operating parameters of the compressors and the phase current peak values ​​of the compressors meet the preset conditions of the preset number of times by detecting the operating parameters of the compressors and the phase current of the compressors. When the stop valve is not opened, the changes in the operating parameters of the compressors and the phase current of the compressors are significantly different from the changes in the corresponding operating parameters and the phase current of the compressors when the indoor motor is blocked or the power supply voltage is extremely low. Therefore, by detecting the operating parameters of the compressors and the phase current of the compressors, when they meet the preset conditions, the stop valve failure is determined, which can avoid misjudgment of the fault caused by the compressor shutdown due to the use scenarios such as the indoor motor blocking or the power supply voltage being extremely low, thereby improving the accuracy of the stop valve failure not opening, reducing the air conditioner locking caused by misjudgment, thereby reducing user complaints, and controlling the compressor to shut down when the operating parameters of the compressors and the current peak values ​​of the compressors meet the preset conditions, without waiting for the overcurrent protection shutdown, which can make the protection timing earlier.

[0231] In some embodiments, it is determined whether the operating parameters of N compressors and the peak value of the phase current of the compressors meet the preset conditions, and the difference between the operating parameters of the compressors at a later moment and the operating parameters of the compressors at a previous moment is calculated to obtain the difference between the operating parameters of N-1 compressors; when the difference between the operating parameters of the compressors at a later moment and the operating parameters of the compressors at a previous moment is positive, it is considered that the operating parameters of the compressors are on an increasing trend, and the operating parameters of the N compressors all exceed the first preset parameter threshold, and the differences of the N-1 operating parameter values ​​are all greater than the second preset parameter threshold, and the compressor current peak value exceeds the preset current threshold, it is determined that the N compressor operating parameter values ​​and the compressor current peak value meet the preset conditions, after determining the compressor operating parameters and the compressor current peak value, the above parameters are compared with the first preset parameter threshold, and the difference between the operating parameters of two adjacent compressors is compared with the second preset parameter threshold, and when the compressor current peak value exceeds the preset current threshold, it is considered that the compressor operating parameters and the compressor phase current meet the preset conditions.

[0232] In some embodiments, taking the operating parameter of the compressor as the phase current of the compressor as an example, when determining whether the operating parameters of N compressors and the peak value of the phase current of the compressor meet the preset conditions, the difference between the phase current of the compressor at a later moment and the phase current of the compressor at a previous moment is calculated, for example, the difference of I(n)- I(n-1), I(n-1)- I(n-2)…I(2) - I(1) is calculated, and the difference of the phase current of N-1 compressors is calculated by analogy. At this time, it is determined whether the above differences are all positive. If the above differences are all positive, it is considered that the phase current of the compressor at a later moment is greater than the phase current of the compressor at a previous moment, and the operating parameters of the N compressors all exceed the first preset parameter threshold, for example, the phase current of the compressor shows an increasing trend and I(n)>I(n-1)>I(n-2)>…I(1)>I1, and the difference between the phase current of the compressor at a later moment and the phase current of the compressor at a previous moment is greater than the second preset parameter threshold, the second preset parameter threshold is, for example, recorded as I2, that is, I(n)- I(n-1)>I2, I(n-1)- I(n-2)>I2, and so on, I(2) - I(1)>I2, and the current peak of the compressor exceeds the preset current threshold, which is, for example, Imax, that is, the current peak of the compressor ≥Imax, that is, Fig.10 (c) shows the phase current variation law. When the above conditions are met, it is determined that the operating parameter values ​​of the N compressors and the compressor current peak values ​​meet the preset conditions. By judging the operating parameters of the compressors and the compressor current peak values, the fault detection of the stop valve can be realized according to the judgment results.

[0233] In some embodiments, when determining the operating parameters of N compressors and the phase current peak values ​​of the compressors, within a second preset time, it is determined whether the operating parameters of the compressors are greater than a first preset parameter threshold value. If so, a reference time for the operation of the compressors is determined, and the reference time is used as a reference time 0 point. The operating parameters of the N compressors and the peak current values ​​of the compressors are determined based on the reference time. When the operating parameters of the compressors are greater than the first preset parameter threshold value, the reference time is determined to facilitate determination of the operating parameters of the compressors based on the reference time.

[0234] In some embodiments, when determining the operating parameters of N compressors and the phase current peak values ​​of the compressors, it is necessary to detect the phase current of the compressors within a second preset time, for example, within 0-t1 minutes, when the outdoor controller of the air conditioner is powered on for the first time and the heating operation is in progress. When the phase current of the compressor is greater than the first preset parameter threshold, the reference time of the compressor operation is determined. The first preset parameter threshold is, for example, recorded as I1, that is, when the phase current of the compressor is ≥I1, this moment is used as the reference time of the compressor operation, that is, the reference time 0, and the operating parameters and the peak current values ​​of the compressors of the N compressors are determined based on the reference time 0. By judging whether the operating parameters of the compressors are greater than the first preset parameter threshold within the second preset time, the reference time of the compressor operation is determined, so that the operating parameters and the peak current values ​​of the compressors of the N compressors are determined based on the reference time, so as to provide a basis for the fault judgment of the stop valve.

[0235] In some embodiments, when the operating parameters of N compressors and the peak current of the compressors are obtained according to the reference time, the operating parameters of the compressors at the reference time are determined; with the reference time as the time starting point and a third preset interval time as the interval, N-1 compressor operating parameters are obtained, and the compressor peak current is obtained; N compressor operating parameters are determined according to the compressor operating parameter values ​​at the reference time and the N-1 compressor operating parameters, wherein the third preset interval time is less than the first low temperature preset time.

[0236] In some embodiments, after determining a reference time of the compressor, the time is used as reference time 0, and the operating parameters of the compressor at this time are detected. The operating parameters of the compressor at the reference time are, for example, recorded as I(1), and the reference time is used as the starting point, and a third preset time is used as an interval, for example, every △t time, to detect and obtain the operating parameters of the compressor. For example, the operating parameters of the compressor obtained every △t time are recorded as I(2), I(3)..., I(n), I(n-1), respectively, and N compressor operating parameter values ​​are determined based on the compressor operating parameters at the reference time and N-1 compressor operating parameter values, so as to facilitate the detection of stop valve faults based on the operating parameters of the N compressors and the compressor peak current.

[0237] In some embodiments, when the operating parameters of N compressors and the peak value of the phase current of the compressors do not meet the preset conditions, the compressors are controlled to continue running until the continuous running time of the compressors reaches a third preset time, and the operating parameters of the compressors and the peak value of the phase current of the compressors are no longer detected to see whether they meet the preset conditions, wherein the third preset time is greater than the first low-temperature preset time. If the operating parameters of the compressors and the phase current of the compressors do not meet the preset conditions within the specified time, the running time of the compressors is timed, and when the running time reaches the third preset time, it is considered that the stop valve detection conditions are not met, and the stop valve does not have a non-opening fault.

[0238] In some embodiments, the air conditioner starts heating operation, and the operating parameters of N compressors and the phase current peak values ​​of the compressors are judged. When the operating parameters of the compressors and the phase current peak values ​​of the compressors do not meet the preset conditions, the compressors are controlled to remain in the on state, and the continuous operation time of the compressors is timed until the continuous operation time of the compressors reaches the third preset time, and it is considered that the stop valve has not failed to open. At this time, the operating parameters of the compressors and the current peak values ​​of the compressors are no longer detected, that is, it is no longer judged whether the stop valve has failed to open, and all data related to the judgment of the stop valve failure is cleared. By obtaining the continuous operation time of the compressors, and when the continuous operation time of the compressors reaches the third preset time, the air conditioner is no longer controlled to execute the stop valve protection strategy, it is possible to avoid misjudgment of stop valve failures caused by external unknown environments and unknown electromagnetic interference, thereby improving the reliability of stop valve judgment.

[0239] In some embodiments, when the operating parameters of the compressor and the current peak of the compressor do not meet the preset conditions for a preset number of times, the controller is further configured to: control the compressor to continue running, and count the running time of the compressor, until the cumulative running time of the compressor reaches the fourth movement preset time, and no longer detect whether the operating parameters of the compressor and the phase current peak of the compressor meet the preset conditions, wherein the fourth movement preset time is greater than the third preset time, if the fault count of the stop valve does not reach the preset number of times, for example, when the fault count of the stop valve is 1, the compressor is controlled to stop, but when it is determined again whether the preset conditions are met, it is detected that the operating parameters of the compressor and the phase current peak of the compressor do not meet the preset conditions, then the running time of the compressor is counted, and when the cumulative running time of the compressor reaches the fourth movement preset time, it is considered that the preset conditions are not met, and the stop valve does not have a non-opening fault.

[0240] In some embodiments, when the air conditioner detects the operating parameters of the compressor and the current peak of the compressor again, if the operating parameters of the compressor and the current peak of the compressor do not meet the preset conditions of the preset number of times, the compressor is controlled to continue running, and the running time of the compressor is timed until the cumulative running time of the compressor reaches the fourth movement preset time, and the operating parameters of the compressor and the current peak of the compressor are no longer detected. By obtaining the cumulative running time of the compressor and no longer controlling the air conditioner to execute the stop valve protection strategy when the cumulative running time of the compressor reaches the fourth movement preset time, the misjudgment of the stop valve failure caused by the unknown external environment and unknown electromagnetic interference can be avoided, thereby improving the reliability of the stop valve judgment.

[0241] It is understandable that, under normal circumstances, the stop valve failure to open may only occur once. When the air conditioner is not in use, the user will actively cut off the power to the air conditioner, or even if the indoor unit is powered on, when it is not turned on, the indoor controller will automatically cut off the power to the outdoor controller. Once the outdoor controller is powered off, the operating parameters of the compressor, the coil temperature value of the indoor heat exchanger, and the data of the air conditioner's execution of the stop valve protection strategy will all be lost. Therefore, each time the outdoor controller is powered on again, a detection and judgment process of the stop valve failure to open will be performed.

[0242] In some embodiments, when the operating parameters of the compressor and the current peak of the compressor meet the preset conditions for a preset number of times, after controlling the compressor to stop, the controller is also configured to: issue an alarm message of a stop valve failure, and control the compressor to stop and no longer start automatically.

[0243] In some embodiments, when the operating parameters of the compressor and the current peak of the compressor meet the preset conditions for a preset number of times, that is, the operating parameters of the compressor at a later moment are greater than the operating parameters of the compressor at a previous moment, and the difference between the N-1 operating parameter values ​​exceeds the first preset parameter threshold, and the number of times the compressor current peak exceeds the preset current peak meets the preset number of times, for example, twice, at this time, it is determined that the stop valve is not open, and an alarm message of a stop valve failure is issued, and the compressor is controlled not to start automatically.

[0244] In some embodiments, the compressor operating parameter includes: any one of the phase current of the compressor, the input power of the compressor, the whole input power of the air conditioner, and the whole input current of the air conditioner.

[0245] In some embodiments, the operating parameters of the compressor can be any one of the effective value of the compressor, the compressor input power, the whole machine input power of the air conditioner and the whole machine input current of the air conditioner. It can be understood that when the air conditioner is running in heating mode, the stop valve is closed and the refrigerant is compressed in a very small space, causing the exhaust pressure to rise sharply and the suction pressure to drop sharply, so that the suction and exhaust pressure difference increases sharply, and then causes the system load to increase sharply, and act on the compressor drive control. In the drive control of the compressor, the increase in load may cause the compressor input power to increase, the compressor phase current to increase at the same voltage, the whole machine input power to increase, the whole machine input current to increase at the same voltage, etc. Therefore, any one of the above can be selected as the operating parameter of the compressor.

[0246] At present, the compressor uses a permanent magnet synchronous motor. The general FOC algorithm needs to transform the coordinate of the current to convert the compressor phase current in the rotating coordinate system into the D-axis and Q-axis currents in the stationary coordinate system, and control the D-axis and Q-axis currents. When the phase current of the compressor increases, the corresponding D-axis current and Q-axis current also increase accordingly. The essence of the FOC algorithm is to combine the three-way current vectors and then decompose them into two components that are perpendicular and parallel to the stationary coordinate system. The D-axis current and Q-axis current can be obtained by calculating and transforming the phase current in the rotating coordinate system through a function, that is, the D-axis current and Q-axis current are the currents after the phase current has undergone coordinate transformation. Therefore, using the D-axis current, the Q-axis current, or a combination of the D-axis and Q-axis as the operating parameters of the compressor also has the same effect.

[0247] For example, within the first preset time, such as 40 seconds, it is detected that the phase current of the compressor exceeds the first preset parameter threshold, such as exceeding 12A, then the phase current of the compressor continues to be detected; it is also possible to detect that the input power of the compressor exceeds the first preset parameter threshold, such as exceeding 4.2W at 40 seconds, then the input power of the compressor continues to be detected; it is also possible to detect that the whole input power of the air conditioner exceeds the first preset parameter threshold, such as exceeding 4.3W at 40 seconds, then the whole input power of the air conditioner continues to be detected; it is also possible to detect that the whole input current of the air conditioner exceeds the first preset parameter threshold, such as exceeding 18A at 40 seconds, then the whole input current of the air conditioner continues to be detected; it is also possible to detect that the Q-axis current of the compressor exceeds the first preset parameter threshold, such as exceeding 10A at 40 seconds, then the Q-axis current of the compressor continues to be detected.

[0248] The following is an example of the fault detection of the stop valve, and the parameters of the air conditioner are set as follows.

[0249] Detection cycle n=4, second preset time t1=1min, third preset interval time interval △t=1s, third preset time t2=10min, fourth movement preset time t3=30min, first preset parameter threshold I1=12A, second preset parameter threshold I2=1A, preset number i=2, preset current threshold Imax=25A. The above parameters can be set as needed.

[0250] In some embodiments, when the outdoor controller is powered on for the first time and runs in heating mode, the compressor starts, and the controller detects the indoor ambient temperature Tin0 = 20°C, the indoor coil temperature Tc0 = 21°C, the outdoor ambient temperature Tout0 = 15°C, the outdoor coil temperature Te0 = 15°C, and the exhaust temperature Td0 = 15°C at the start-up time, and detects the phase current of the compressor in real time. If at the moment of 40s, which is less than the second preset time t1=1min, the detected phase current I(1) is 12A, which is equal to the second preset parameter threshold value I1=12A. After the third preset time △t, the detected phase current is recorded as I(2)=13.2A>12A. After another 1s, the detected phase current is recorded as I(3)=14.6A>12A. After another 1s, the detected phase current is recorded as I(4)=15.8A>12A. I(4)-I(3)=1.2A>1A, I(3)-I(2)=1.4A>1A, I(2)-I(1)=1.2A>1A are calculated respectively. At this time, the peak current of the compressor is 26A greater than 25A, which satisfies all the possible faults of the shut-off valve not being opened. The compressor is actively stopped and counted once.

[0251] 3min later, the compressor is restarted and the phase current and other data of the compressor are continuously detected. If the phase current detected at 28s is 12A, it is recorded as I(1)=12A. 1s later, the phase current detected is recorded as I(2)=13.2A>12A; 1s later, the phase current detected is recorded as I(3)=14.6A>12A; 1s later, the phase current detected is recorded as I(4)=15.8A>12A; I(4)- I(3)=1.2A>1A, I(3)- I(2) =1.4A>1A, I(2)- I(1) =1.2A>1A, and the peak current of the compressor is 26.5A>25A at this time, which satisfies all the possible reasons for the stop valve not opening fault. The compressor is automatically stopped and counted once until the preset number is reached, for example, when it reaches 2 times, the stop valve not opening fault is reported and it will not restart automatically.

[0252] In some embodiments, when the outdoor unit controller is powered on for the first time and operates in heating mode, the compressor starts. The controller detects the indoor ambient temperature Tin0=20°C, the indoor coil temperature Tc0=21°C, the outdoor ambient temperature Tout0=15°C, the outdoor coil temperature Te0=15°C, and the exhaust temperature Td0=15°C at the start time, and detects the phase current of the compressor in real time. If the phase current is detected to be 12A at 59s, it is recorded as I(1)=12A; 1s later, the phase current I(2)=12.2A>12A is detected; 1s later, the phase current I(3)=12.4A>12A is detected; 1s later, the phase current I(4)=12.2A>12A is detected; I(4)-I(3)=0.2A<1A, I(3)-I(2)=0.2A<1A, I(2)-I(1) are calculated respectively. =-0.2A<1A, but the peak current of the compressor is 24, which is less than 25. If all the conditions are not met, it may be that the stop valve is not opened, and the compressor continues to run.

[0253] The compressor runs until 10 minutes, the third preset time t2=10 minutes, and there is no abnormality, so the stop valve failure will no longer be judged.

[0254] According to the air conditioner of some embodiments of the present application, when the air conditioner is powered on for the first time and the heating operation is started, the operating parameters of N compressors and the phase current peak values ​​of the compressors are analyzed. Since the operating parameters of the compressors and the phase current peak values ​​of the compressors meet a specific rule when the stop valve is not opened, the operating parameters of the compressors and the phase current peak values ​​of the compressors meet the preset conditions of the preset number of times by detecting the operating parameters of the compressors and the phase current of the compressors. When the stop valve is not opened, the changes in the operating parameters of the compressors and the phase current of the compressors are significantly different from the changes in the corresponding operating parameters and the phase current of the compressors when the indoor motor is blocked or the power supply voltage is extremely low. Therefore, by detecting the operating parameters of the compressors and the phase current of the compressors, when they meet the preset conditions, the stop valve failure is determined, which can avoid misjudgment of the fault caused by the compressor shutdown due to the use scenarios such as the indoor motor blocking or the power supply voltage being extremely low, thereby improving the accuracy of the stop valve failure not opening, reducing the air conditioner locking caused by misjudgment, thereby reducing user complaints, and controlling the compressor to shut down when the operating parameters of the compressors and the current peak values ​​of the compressors meet the preset conditions, without waiting for the overcurrent protection shutdown, which can make the protection timing earlier.

[0255] The following is an illustration of the air conditioner stop valve fault detection method according to some embodiments of the present application.

[0256] like Fig.12 As shown, the air conditioner stop valve fault detection method of some embodiments of the present application includes at least step S1 and step S.

[0257] Step S41, when the air conditioner is powered on for the first time and starts heating operation, the operating parameters of N compressors and the phase current peak values ​​of the N compressors are determined.

[0258] Step S42, determining whether the operating parameters of the N compressors and the phase current peak values ​​of the N compressors meet preset conditions.

[0259] Step S43: if the conditions are met, the compressor is controlled to stop, and after the first low temperature preset time, the operating parameters of the N compressors and the phase current peak values ​​of the N compressors are determined again.

[0260] Step S44, determining whether the operating parameters of the N compressors and the phase current peak values ​​of the N compressors meet preset conditions for a preset number of times.

[0261] Step S45, determining that the stop valve is faulty, and controlling the compressor to shut down.

[0262] Step S46, controlling the compressor to continue running.

[0263] Step S47, detecting the running time of the compressor, and when the running time of the compressor reaches the fourth movement preset time, no longer detecting whether the preset condition is met.

[0264] According to the shut-off valve fault detection method for air conditioners in some embodiments of the present application, when the air conditioner is powered on for the first time and the heating operation is turned on, the operating parameters of N compressors and the peak values ​​of the phase currents of the compressors are analyzed. Since the operating parameters of the compressors and the peak values ​​of the phase currents of the compressors satisfy a specific rule when the shut-off valves are not opened, it is determined that the shut-off valve has a non-opening fault by detecting the operating parameters of the compressors and the phase currents of the compressors when the operating parameters of the compressors and the peak values ​​of the phase currents of the compressors satisfy the preset conditions for the preset number of times. Since the changes in the operating parameters of the compressors and the phase currents of the compressors when the shut-off valves are not opened are consistent with the indoor motor blockage, the shut-off valves are not opened. When the power supply voltage is too low, there are obvious differences in the changes in the corresponding compressor operating parameters and the compressor phase current. Therefore, by detecting the compressor operating parameters and the compressor phase current, when they meet the preset conditions, the stop valve fault is determined, which can avoid the misjudgment of the compressor shutdown caused by usage scenarios such as indoor motor jam or ultra-low power supply voltage, thereby improving the accuracy of the stop valve failure to open, reducing the air conditioner lock caused by misjudgment, thereby reducing user complaints, and controlling the compressor to stop when the compressor operating parameters and the compressor current peak meet the preset conditions, without waiting for the overcurrent protection shutdown, which can make the protection timing earlier.

[0265] In some embodiments, determining that the operating parameters of N compressors and the phase current peak of the compressor meet preset conditions includes: calculating the difference between the operating parameters of the compressor at a later moment and the operating parameters of the compressor at a previous moment, and obtaining the difference between the operating parameters of N-1 compressors; when the difference between the operating parameters of the compressor at a later moment and the operating parameters of the compressor at a previous moment is positive, and the differences between the N-1 operating parameter values ​​are all greater than the first preset parameter threshold, and the compressor current peak exceeds the preset current peak, determining that the N compressor operating parameters and the compressor current peak meet the preset conditions.

[0266] In some embodiments, taking the operating parameter of the compressor as the phase current of the compressor as an example, when determining whether the operating parameters of N compressors and the peak value of the phase current of the compressor meet the preset conditions, the difference between the phase current of the compressor at a later moment and the phase current of the compressor at a previous moment is calculated, for example, the difference of I(n)- I(n-1), I(n-1)- I(n-2)…I(2) - I(1) is calculated, and the difference of the phase current of N-1 compressors is calculated by analogy. At this time, it is determined whether the above differences are all positive. If the above differences are all positive, it is considered that the phase current of the compressor at a later moment is greater than the phase current of the compressor at a previous moment, that is, it is considered that the phase current of the compressor shows an increasing trend, for example, I(n)>I(n-1)>I(n-2)>…I(1), and the difference between the phase current of the compressor at a later moment and the phase current of the compressor at a previous moment is greater than a first preset parameter threshold, which is recorded as I2, for example, I(n)- I(n-1)>I2, I(n-1) - I(n-2)>I2, and so on, I(2) - I(1)>I2, and the current peak of the compressor exceeds the preset current peak, which is recorded as Imax, that is, the current peak of the compressor ≥Imax, that is, Figure 7 The phase current variation law shown in FIG. 1 shows that when the above conditions are met, it is determined that the operating parameter values ​​of the N compressors and the compressor current peak values ​​meet the preset conditions. By judging the operating parameters of the compressors and the compressor current peak values, the fault detection of the stop valve can be realized according to the judgment results.

[0267] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example.

[0268] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. An air conditioner, characterized in that: include: A refrigerant circulation loop allows the refrigerant to circulate in the compressor, condenser, expansion valve and evaporator in the circulation loop; an outdoor heat exchanger and an indoor heat exchanger, wherein one works as the condenser and the other works as the evaporator; Indoor coil temperature sensor, used to detect indoor coil temperature; An outdoor unit, the outdoor unit comprising: Outdoor housing; A compressor, disposed in the outdoor housing, for compressing low-temperature and low-pressure refrigerant gas into high-temperature and high-pressure refrigerant gas and discharging the refrigerant gas to the condenser; A stop valve, the stop valve is arranged in the outdoor unit housing and is used to open or close the refrigerant circulation circuit; A controller, for determining the operating parameters of N compressors and the indoor coil temperatures of N indoor heat exchangers when the air conditioner is powered on for the first time and the air conditioner is turned on for heating operation; When the operating parameters of the N compressors and the N indoor coil temperatures meet the preset conditions, the compressor is controlled to stop, and after the first low temperature preset time, the compressor is restarted, and the operating parameters of the N compressors and the N indoor coil temperatures are determined again, and when the operating parameters of the N compressors and the N indoor coil temperatures meet the preset conditions for a preset number of times, the stop valve failure is determined, and the compressor is controlled to stop, wherein the operating parameters of the compressor and the indoor coil temperature at the reference time are used as a reference, and the operating parameters of the compressor and the indoor coil temperature are obtained at regular intervals until the operating parameters of the N compressors and the N indoor coil temperatures are obtained; When it is determined that the operating parameters of the N compressors and the N indoor coil temperatures meet the preset conditions, the controller is configured as follows: Calculate the difference between the operating parameter value of the compressor at a later moment and the operating parameter of the compressor at a previous moment to obtain N-1 differences in the operating parameters of the compressor, and calculate the temperature difference between the N indoor coil temperatures and the indoor initial coil temperature at the time of starting the compressor to obtain N temperature differences; When the differences between the operating parameters of the compressor at a later moment and the operating parameters of the compressor at a previous moment are all positive, and the operating parameters of the N compressors are all greater than the first preset parameter threshold, and the differences of the N-1 operating parameters are all greater than the second preset parameter threshold, and the N temperature differences are all less than the third preset parameter threshold, it is determined that the operating parameter values ​​of the N compressors and the N coil temperatures meet the preset conditions.

2. The air conditioner according to claim 1, characterized in that: When determining the operating parameters of N compressors and N indoor coil temperatures, the controller is configured as follows: Within a second preset time, determining whether the operating parameter of the compressor is greater than the first preset parameter threshold; If yes, determining a reference time for the compressor to operate; The operating parameters of the N compressors and the N indoor coil temperatures are determined according to the reference time.

3. The air conditioner according to claim 2, characterized in that: Determine the operating parameters of N compressors and the N indoor coil temperatures according to the reference time, and the controller is specifically configured as follows: Determining the operating parameters of the compressor and the indoor coil temperature at the reference time; Taking the reference time as the time starting point and taking the third preset interval time as the interval, obtaining N-1 operating parameters of the compressors and N-1 indoor coil temperatures; The N compressor operating parameters are determined based on the compressor operating parameters at the reference time and the N-1 compressor operating parameters, and the N indoor coil temperatures are determined based on the indoor coil temperature at the reference time and the N-1 indoor coil temperatures, wherein the third preset interval time is less than the first low temperature preset time.

4. The air conditioner according to claim 1, characterized in that: When the operating parameters of the N compressors and the temperatures of the N indoor coils do not meet the preset conditions, the controller is further configured to: The compressor is controlled to run continuously until the continuous running time of the compressor reaches a third preset time, and the running parameters of the compressor and the indoor coil temperature are no longer detected to see whether they meet the preset conditions, wherein the third preset time is greater than the first low temperature preset time.

5. The air conditioner according to claim 4, characterized in that: When the operating parameters of the N compressors and the N indoor coil temperatures do not meet the preset conditions for a preset number of times, the controller is further configured to: The compressor is controlled to continue running, and the running time of the compressor is counted until the accumulated running time of the compressor reaches a fourth movement preset time, and whether the running parameters of the compressor and the indoor coil temperature meet the preset conditions is no longer detected, wherein the fourth movement preset time is greater than the third preset time.

6. The air conditioner according to claim 1, characterized in that: When the operating parameters of the N compressors and the N indoor coil temperatures meet the preset conditions for a preset number of times, after the compressors are controlled to stop, the controller is further configured to: An alarm message of the stop valve failure is issued, and the compressor is controlled to stop and not start automatically.

7. The air conditioner according to claim 1, characterized in that: The compressor operation parameter includes: any one of the phase current of the compressor, the input power of the compressor, the whole machine input power of the air conditioner and the whole machine input current of the air conditioner.

8. A method for detecting a stop valve failure of an air conditioner, characterized in that: include: When the air conditioner is powered on for the first time and starts heating operation, the operating parameters of N compressors and the indoor coil temperatures of N indoor heat exchangers are determined; When the operating parameters of the N compressors and the N indoor coil temperatures meet the preset conditions, the compressor is controlled to stop, and after the first low temperature preset time, the compressor is restarted, and the operating parameters of the N compressors and the N indoor coil temperatures are determined again, and when the operating parameters of the N compressors and the N indoor coil temperatures meet the preset conditions for a preset number of times, the stop valve is determined to be faulty, and the compressor is controlled to stop, wherein the operating parameters of the compressor and the indoor coil temperature at the reference time are used as a reference, and the operating parameters of the compressor and the indoor coil temperature are obtained at regular intervals until the operating parameters of the N compressors and the N indoor coil temperatures are obtained; When determining that the operating parameters of the N compressors and the temperatures of the N indoor coils meet preset conditions, it includes: Calculating the difference between the operating parameter value of the compressor at a later moment and the operating parameter of the compressor at a previous moment to obtain N-1 differences in the operating parameters of the compressor, and calculating the temperature difference between N indoor coil temperatures and the indoor initial coil temperature to obtain N temperature differences; When the differences between the operating parameters of the compressor at a later moment and the operating parameters of the compressor at a previous moment are all positive, and the operating parameters of the compressor are all greater than the first preset parameter threshold, and the differences of N-1 operating parameters all exceed the second preset parameter threshold, and the N temperature differences do not exceed the third preset parameter threshold, it is determined that the operating parameter values ​​of the N compressors and the N coil temperatures meet the preset conditions.

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